ring chromosomes

Summary

Summary: Aberrant chromosomes with no ends, i.e., circular.

Top Publications

  1. ncbi Supernumerary ring chromosome 7 mosaicism: case report, investigation of the gene content, and delineation of the phenotype
    K D Lichtenbelt
    Department of Biomedical Genetics, University Medical Centre Utrecht, Utrecht, The Netherlands
    Am J Med Genet A 132:93-100. 2005
  2. ncbi Unique genomic structure and distinct mitotic behavior of ring chromosome 21 in two unrelated cases
    H Z Zhang
    Department of Genetics, Yale School of Medicine, New Haven, CT 06520 8005, USA
    Cytogenet Genome Res 136:180-7. 2012
  3. ncbi Genetics of dermatofibrosarcoma protuberans family of tumors: from ring chromosomes to tyrosine kinase inhibitor treatment
    Nicolas Sirvent
    Service de Pediatrie, Centre Hospitalier Universitaire de Nice, Nice, France
    Genes Chromosomes Cancer 37:1-19. 2003
  4. ncbi Coamplification of 12p11 and 12q13 approximately q22 in multiple ring chromosomes in a spindle cell sarcoma resolved by novel multicolor fluorescence in situ hybridization analysis
    Valia S Lestou
    Department of Pathology and Laboratory Medicine, British Columbia Cancer Agency, R, British Columbia, Vancouve, Canada
    Cancer Genet Cytogenet 139:44-7. 2002
  5. ncbi Prenatal diagnosis of ring chromosome 6 in a fetus with cerebellar hypoplasia and partial agenesis of corpus callosum: case report and review of the literature
    Joris Andrieux
    Laboratoire de Génétique Médicale Barre Nord Hôpital Jeanne de Flandre, CHRU Lille, 59037 Lille Cedex, France
    Eur J Med Genet 48:199-206. 2005
  6. pmc Telomere-independent homologue pairing and checkpoint escape of accessory ring chromosomes in male mouse meiosis
    Thierry Voet
    Human Genome Laboratory, Department of Human Genetics, Flanders Interuniversity Institute for Biotechnology, University of Leuven, Belgium
    J Cell Biol 162:795-807. 2003
  7. ncbi FOXC1 gene deletion is associated with eye anomalies in ring chromosome 6
    Hui Z Zhang
    Department of Genetics, Yale University School of Medicine, New Haven, Connecticut 06520, USA
    Am J Med Genet A 124:280-7. 2004
  8. pmc Telomeres act autonomously in maize to organize the meiotic bouquet from a semipolarized chromosome orientation
    Peter M Carlton
    Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA
    J Cell Biol 157:231-42. 2002
  9. ncbi High-resolution array CGH analysis of salivary gland tumors reveals fusion and amplification of the FGFR1 and PLAG1 genes in ring chromosomes
    F Persson
    Lundberg Laboratory for Cancer Research, Department of Pathology, Sahlgrenska University Hospital, Goteborg University, Goteborg, Sweden
    Oncogene 27:3072-80. 2008
  10. ncbi Ring chromosome 6 in three fetuses: case reports, literature review, and implications for prenatal diagnosis
    Maik Urban
    Institut fur Medizinische Genetik, Universitatsklinikum Charite, Humboldt Universität zu, Berlin, Germany
    Am J Med Genet 108:97-104. 2002

Research Grants

  1. GENETIC STUDIES OF HUMAN CELLS
    BARBARA MIGEON; Fiscal Year: 2001
  2. RIBOSOMAL GENE REPLICATION DURING MAGNIFICATION
    SHARYN ENDOW; Fiscal Year: 1990
  3. Schizophrenia Predisposition in 22q11 Deletion Syndrome
    Vandana Shashi; Fiscal Year: 2005
  4. Molecular Analysis of Alagille Syndrome
    NANCY SPINNER; Fiscal Year: 2006

Detail Information

Publications201 found, 100 shown here

  1. ncbi Supernumerary ring chromosome 7 mosaicism: case report, investigation of the gene content, and delineation of the phenotype
    K D Lichtenbelt
    Department of Biomedical Genetics, University Medical Centre Utrecht, Utrecht, The Netherlands
    Am J Med Genet A 132:93-100. 2005
    ..23. We speculate that the effects on speech acquisition are mediated by the supernumerary copies of the STX1A and LIMK1 genes, which are both located in this region and known to suppress neurite growth when overexpressed in vitro...
  2. ncbi Unique genomic structure and distinct mitotic behavior of ring chromosome 21 in two unrelated cases
    H Z Zhang
    Department of Genetics, Yale School of Medicine, New Haven, CT 06520 8005, USA
    Cytogenet Genome Res 136:180-7. 2012
    ..A cytogenomic approach is proposed for characterizing the genomic structure and mitotic instability of ring chromosome abnormalities...
  3. ncbi Genetics of dermatofibrosarcoma protuberans family of tumors: from ring chromosomes to tyrosine kinase inhibitor treatment
    Nicolas Sirvent
    Service de Pediatrie, Centre Hospitalier Universitaire de Nice, Nice, France
    Genes Chromosomes Cancer 37:1-19. 2003
    ..At the cytogenetic level, DP cells are characterized by either supernumerary ring chromosomes, which have been shown by using fluorescence in situ hybridization techniques to be derived from chromosome ..
  4. ncbi Coamplification of 12p11 and 12q13 approximately q22 in multiple ring chromosomes in a spindle cell sarcoma resolved by novel multicolor fluorescence in situ hybridization analysis
    Valia S Lestou
    Department of Pathology and Laboratory Medicine, British Columbia Cancer Agency, R, British Columbia, Vancouve, Canada
    Cancer Genet Cytogenet 139:44-7. 2002
    ..analysis demonstrated a complex karyotype with a der(6), a small marker and five, different in size, ring chromosomes. Fluorescence in situ hybridization (FISH), multiplex FISH, and multicolor banding analysis was used to ..
  5. ncbi Prenatal diagnosis of ring chromosome 6 in a fetus with cerebellar hypoplasia and partial agenesis of corpus callosum: case report and review of the literature
    Joris Andrieux
    Laboratoire de Génétique Médicale Barre Nord Hôpital Jeanne de Flandre, CHRU Lille, 59037 Lille Cedex, France
    Eur J Med Genet 48:199-206. 2005
    ..Magnetic resonance imaging (MRI) confirmed this, but showed a partial corpus callosum agenesis, leading to amniocentesis and revealing the chromosomal abnormality. Imaging features were correlated with autopsy findings...
  6. pmc Telomere-independent homologue pairing and checkpoint escape of accessory ring chromosomes in male mouse meiosis
    Thierry Voet
    Human Genome Laboratory, Department of Human Genetics, Flanders Interuniversity Institute for Biotechnology, University of Leuven, Belgium
    J Cell Biol 162:795-807. 2003
    ..Our findings indicate a telomere-independent mechanism for pairing of mammalian MCs, illuminate escape routes to meiotic checkpoints, and give clues for genetic engineering of germ line-permissive chromosomal vectors...
  7. ncbi FOXC1 gene deletion is associated with eye anomalies in ring chromosome 6
    Hui Z Zhang
    Department of Genetics, Yale University School of Medicine, New Haven, Connecticut 06520, USA
    Am J Med Genet A 124:280-7. 2004
    ..We recommend ophthalmology, audiology, cardiology, and central nervous system examinations be part of the routine evaluation for children with a ring chromosome 6...
  8. pmc Telomeres act autonomously in maize to organize the meiotic bouquet from a semipolarized chromosome orientation
    Peter M Carlton
    Department of Molecular and Cell Biology, University of California at Berkeley, Berkeley, CA 94720, USA
    J Cell Biol 157:231-42. 2002
    ..By examining telocentric and ring chromosomes, we have tested the cis-acting requirements for participation in the bouquet...
  9. ncbi High-resolution array CGH analysis of salivary gland tumors reveals fusion and amplification of the FGFR1 and PLAG1 genes in ring chromosomes
    F Persson
    Lundberg Laboratory for Cancer Research, Department of Pathology, Sahlgrenska University Hospital, Goteborg University, Goteborg, Sweden
    Oncogene 27:3072-80. 2008
    We have previously identified a subgroup of pleomorphic salivary gland adenomas with ring chromosomes of uncertain derivation...
  10. ncbi Ring chromosome 6 in three fetuses: case reports, literature review, and implications for prenatal diagnosis
    Maik Urban
    Institut fur Medizinische Genetik, Universitatsklinikum Charite, Humboldt Universität zu, Berlin, Germany
    Am J Med Genet 108:97-104. 2002
    ..This makes prognostic counseling of parents difficult and unsatisfactory. Serial targeted ultrasound examinations, especially of the brain, are decisive factors in elucidating the prognosis...
  11. ncbi An epileptic case with mosaic ring chromosome 6 and 6q terminal deletion
    Nurten Kara
    Ondokuz Mayis University, Faculty of Medicine, Department of Medical Biology and Genetics, 55139 Samsun, Turkey
    Epilepsy Res 80:219-23. 2008
    b>Ring chromosomes are rare chromosome disorders that arise usually de novo. Children with ring chromosome 6 have a wide range of intellectual functioning and congenital anomalies...
  12. ncbi Molecular characterization of an inherited ring (19) demonstrating ring opening
    Marsha D Speevak
    Division of Genetics, Department of Laboratory Medicine, The Credit Valley Hospital, Mississauga, Ontario, Canada
    Am J Med Genet A 121:141-5. 2003
    b>Ring chromosomes arise following breakage in both chromosome arms and rejoining of the centric segment at the broken ends or by end-to-end fusion of the telomeres...
  13. ncbi Ring chromosome instability evaluation in six patients with autosomal rings
    C P Sodré
    Departamento de Morfologia e Genética da Universidade Federal de São Paulo, Sao Paulo, SP, Brasil
    Genet Mol Res 9:134-43. 2010
    b>Ring chromosomes are often associated with abnormal phenotypes due to loss of genomic material and also because of ring instability at mitosis after sister chromatid exchange events...
  14. ncbi Clinical, cytogenetic and molecular study in a case of r(3) with 3p deletion and review of the literature
    R Santos Guilherme
    Department of Morphology and Genetics, Universidade Federal de Sao Paulo, Brazil
    Cytogenet Genome Res 134:325-30. 2011
    ..This is the first patient with r(3) studied using molecular techniques that determined the exact breakpoints in order to establish a better karyotype-phenotype correlation...
  15. ncbi Inherited ring chromosome 8 without loss of subtelomeric sequences
    Cedric Le Caignec
    Service de Genetique Medicale, Plateau Technique, Centre Hospitalo Universitaire, 9, quai Moncousu, 44093 Nantes Cedex, France
    Ann Genet 47:289-96. 2004
    ..These findings indicate that ring chromosome 8 without loss of subtelomeric sequences can be inherited and that carriers in a same family present with cognitive function ranging from mild mental retardation to normal intelligence...
  16. ncbi Ring chromosome 15: characterization by array CGH
    Ian A Glass
    Department of Pediatrics, University of Washington, M2 9, 4800 Sand Point Way NE, Seattle, 98105, USA
    Hum Genet 118:611-7. 2006
    ..These cases illustrate the utility of array CGH characterization for determining the size of the associated deletion in ring chromosomes and for facilitating phenotype-genotype correlations.
  17. ncbi The structure and dynamics of ring chromosomes in human neoplastic and non-neoplastic cells
    D Gisselsson
    Department of Clinical Genetics, Lund University Hospital, Sweden
    Hum Genet 104:315-25. 1999
    Acquired ring chromosomes have been found in most types of human neoplasia, with a frequency approaching 10% in malignant mesenchymal tumours...
  18. ncbi Characterization of a hotspot region on chromosome 12 for amplification in ring chromosomes in atypical lipomatous tumors
    Domenico Trombetta
    Department of Genetics and Microbiology, University of Bari, Bari, Italy
    Genes Chromosomes Cancer 48:993-1001. 2009
    b>Ring chromosomes are cytogenetic hallmarks of genomic amplification in several bone and soft tissue tumors, in particular atypical lipomatous tumors (ALT)...
  19. ncbi Myxoinflammatory fibroblastic sarcoma with complex supernumerary ring chromosomes composed of chromosome 3 segments
    Atiya Mansoor
    Department of Pathology, Oregon Health and Sciences University, Portland, OR 97239, USA
    Cancer Genet Cytogenet 152:61-5. 2004
    ..We describe here a second case showing supernumerary ring chromosomes, and a derivative chromosome 13, with additional material on the short arm...
  20. ncbi Clinical findings and cytogenetic analysis of small supernumerary ring chromosomes 7: report of two new cases
    Sandra Chantot-Bastaraud
    Service d Histologie, Biologie de la Reproduction et Cytogénétique UPMC EA 1533, Hopital Tenon AP HP, 75020 Paris, France
    Ann Genet 47:241-9. 2004
    ..Both ring chromosomes were labelled by FISH using the Williams Syndrome locus probe (Elastin Gene D7S486)...
  21. ncbi Ring 14 chromosome presenting as early-onset isolated partial epilepsy
    Dorothée Ville
    Department of Pediatric Neurology, Hopital Femme Mere Enfant, Lyon, France
    Dev Med Child Neurol 51:917-22. 2009
    ..Many unanswered questions remain concerning phenotype-genotype correlation and identification of the potential genes and molecular mechanisms responsible for epilepsy in patients with ring 14 syndrome...
  22. ncbi Ring syndrome caused by ring chromosome 7 without loss of subtelomeric sequences
    J R Vermeesch
    Center for Human Genetics, University of Leuven, Belgium
    Clin Genet 62:415-7. 2002
    ....
  23. ncbi Molecular analysis of ring chromosome 20 syndrome reveals two distinct groups of patients
    Laura K Conlin
    Department of Pathology and Laboratory Medicine, The Children s Hospital of Philadelphia, The University of Pennsylvania School of Medicine, 19104, USA
    J Med Genet 48:1-9. 2011
    ..The ring chromosome 20 syndrome (R20) is a rare genetic disorder associated with a refractory electroclinical epilepsy syndrome and variably expressed comorbidities of intellectual disability and dysmorphism...
  24. ncbi Characterization of mosaic supernumerary ring chromosomes by array-CGH: segmental aneusomy for proximal 4q in a child with tall stature and obesity
    Céline Bonnet
    Laboratoire de Génétique EA 3441, Centre Hospitalier Universitaire de Nancy, Vandoeuvre les Nancy, France
    Am J Med Genet A 140:233-7. 2006
    ..2 and including the insulin-like growth factor binding protein 7 (IGFBP7) gene. This finding suggests that postnatal overgrowth observed in our patient might be related to a dosage effect of the IGFBP7 gene...
  25. ncbi Ring chromosome formation as a novel escape mechanism in patients with inverted duplication and terminal deletion
    Jeroen Knijnenburg
    Department of Molecular Cell Biology, Leiden University Medical Center, Leiden, The Netherlands
    Eur J Hum Genet 15:548-55. 2007
    b>Ring chromosomes are rare cytogenetic findings and are associated at phenotypic level with mental retardation and congenital abnormalities...
  26. pmc Telomeric 22q13 deletions resulting from rings, simple deletions, and translocations: cytogenetic, molecular, and clinical analyses of 32 new observations
    J J Luciani
    J Med Genet 40:690-6. 2003
  27. pmc Molecular characterisation of a ring chromosome 22 in a patient with severe language delay: a contribution to the refinement of the subtelomeric 22q deletion syndrome
    P De Mas
    J Med Genet 39:e17. 2002
  28. ncbi Loss of genetic material is more common than gain in acute myeloid leukemia with complex aberrant karyotype: a detailed analysis of 125 cases using conventional chromosome analysis and fluorescence in situ hybridization including 24-color FISH
    Claudia Schoch
    Department of Internal Medicine III, University Hospital Grosshadern, Ludwig Maximilians University, Munich, Germany
    Genes Chromosomes Cancer 35:20-9. 2002
    ....
  29. ncbi Genomic profiling of bone and soft tissue tumors with supernumerary ring chromosomes using tiling resolution bacterial artificial chromosome microarrays
    M Heidenblad
    Department of Clinical Genetics, Lund University Hospital, Lund, Sweden
    Oncogene 25:7106-16. 2006
    b>Ring chromosomes and/or giant marker chromosomes have been observed in a variety of human tumor types, but they are particularly common in a subgroup of mesenchymal tumors of low-grade or borderline malignancy...
  30. ncbi Early pattern of epilepsy in the ring chromosome 20 syndrome
    Dorothée Ville
    Department of Clinical Neurophysiology, Hopital Necker Enfants Malades, Paris, France
    Epilepsia 47:543-9. 2006
    ..The mode of onset most often remains imprecise. To clarify this onset period, we studied the early-onset features in our personal series and in the reported pediatric cases...
  31. ncbi Association of microcephaly and cafe-au-lait spots in a patient with ring chromosome 12 syndrome
    P R G Zen
    Programa de Pós Graduação em Patologia and Disciplina de Genética Clínica, Fundacao Faculdade Federal de Ciencias Medicas, Rua Sarmento Leite 245 403, Porto Alegre, RS 90050 170, Brazil
    Clin Dysmorphol 14:141-3. 2005
    ..The similarity of our patient to those previously described suggests that the ring chromosome 12 syndrome can be delineated as a distinct entity with characteristic clinical features...
  32. ncbi Molecular and phenotypic characterization of ring chromosome 22
    Aaron R Jeffries
    Department of Neuroscience, Institute of Psychiatry, Denmark Hill, London SE5 8AF, United Kingdom
    Am J Med Genet A 137:139-47. 2005
    ..Internal organ involvement was uncommon. Even though ring chromosomes are reportedly associated with growth abnormalities, only 2 out of 24 individuals showed evidence of growth ..
  33. ncbi Mutational analysis and expression studies of the neurofibromatosis type 2 (NF2) gene in a patient with a ring chromosome 22 and NF2
    H Kehrer-Sawatzki
    Abteilung Humangenetik, Ulm, Germany
    Hum Genet 100:67-74. 1997
    ..The instability of the ring chromosome 22 with the associated loss of tumor suppressor genes on chromosome 22, in particular the loss of the NF2 gene, are assumed to have caused multiple tumorigenesis in this patient...
  34. ncbi Ring chromosome 17: phenotype variation by deletion size
    V Shashi
    Department of Pediatrics Medical Genetics, Wake Forest University School of Medicine, Winston Salem, NC 27157, USA
    Clin Genet 64:361-5. 2003
    ..This classification of ring 17 into two distinct groups based on the size of the deletion and the phenotypic manifestations should facilitate clinical suspicion of this rare chromosomal abnormality...
  35. ncbi Five new subjects with ring chromosome 22
    H A Ishmael
    The Children s Mercy Hospitals and Clinics and University of Missouri Kansas City School of Medicine, Kansas City, MO, USA
    Clin Genet 63:410-4. 2003
    ..Similarly, recessive alleles unmasked by the deletion could also contribute to the phenotype...
  36. ncbi PET evidence for a role of the basal ganglia in patients with ring chromosome 20 epilepsy
    A Biraben
    Service de Neurologie, CHU Pontchaillou, Rennes, France
    Neurology 63:73-7. 2004
    ..The hypothesis that these long-lasting seizures are associated with a reduction of striatal dopamine was addressed in the present study in drug-resistant patients with r(20) epilepsy using PET...
  37. ncbi Mosaicism and phenotype in ring chromosome 20 syndrome
    T Nishiwaki
    Department of Neurology, Nara Medical University, Nara, Japan
    Acta Neurol Scand 111:205-8. 2005
    ..Our results provide important clinical information and prediction for r(20) syndrome...
  38. ncbi Duplications in addition to terminal deletions are present in a proportion of ring chromosomes: clues to the mechanisms of formation
    E Rossi
    Biologia Generale e Genetica Medica, Universita di Pavia, Pavia, Italy
    J Med Genet 45:147-54. 2008
    b>Ring chromosomes are often associated with abnormal phenotypes because of loss of genomic material at one or both ends. In some cases no deletion has been detected and the abnormal phenotype has been attributed to mitotic ring instability...
  39. ncbi Detailed characterization of 12 supernumerary ring chromosomes using micro-FISH and search for uniparental disomy
    B M Anderlid
    Department of Molecular Medicine, Clinical Genetics Unit, Karolinska Institutet, Stockholm, Sweden
    Am J Med Genet 99:223-33. 2001
    Twelve patients with varying degrees of mosaicism for a supernumerary ring chromosome were studied. The ring chromosomes were characterized using microdissection in combination with degenerate nucleotide-primed polymerase chain reaction (..
  40. pmc Constitutional rearrangements of chromosome 22 as a cause of neurofibromatosis 2
    T Tsilchorozidou
    J Med Genet 41:529-34. 2004
  41. ncbi A girl with cutaneous hyperpigmentation, café au lait spots and ring chromosome 15 without significant deletion
    E Morava
    University of Pecs, Medical Faculty, Department of Medical Genetics and Child Development, Pecs, 7623 Hungary
    Genet Couns 14:337-42. 2003
    ..Patchy skin hypopigmentation is a well known nonspecific sign in cytogenetic mosaicism which is commonly seen in ring syndrome...
  42. ncbi Meiotic origin of two ring chromosomes 18 in a girl with developmental delay
    A Baumer
    Institute of Medical Genetics, University of Zurich, Zurich, Switzerland
    Am J Med Genet 113:101-4. 2002
    ..Our results show a paternal origin of the structurally normal chromosome 18 and a maternal origin for both ring chromosomes 18...
  43. ncbi Chromosome 18 replaced by two ring chromosomes of chromosome 18 origin
    K Miller
    Institute of Human Genetics, Hannover Medical University, 30623 Hannover, Germany
    Hum Genet 112:343-7. 2003
    We here describe the first example of the replacement of an autosome by two ring chromosomes originating from the missing chromosome, presented in a patient with a single chromosome 18 and two additional ring chromosomes...
  44. ncbi Mosaic ring 20 with no detectable deletion by FISH analysis: Characteristic seizure disorder and literature review
    Ying S Zou
    Cytogenetics Laboratory, Mayo Clinic, Rochester, Minnesota 55905, USA
    Am J Med Genet A 140:1696-706. 2006
    ....
  45. ncbi Molecular characterization of a de novo ring chromosome 6 in a growth retarded but otherwise healthy woman
    Martina Höckner
    Division of Clinical Genetics, Department of Medical Genetics, Molecular and Clinical Pharmacology, Medical University of Innsbruck, Innsbruck, Austria
    Am J Med Genet A 146:925-9. 2008
    ..Thus this case clearly shows that in patients with ring chromosomes without loss of euchromatic material mitotic instability of the ring chromosome is the most important reason ..
  46. ncbi Ring-20-syndrome and loss of telomeric regions
    D Garcia-Cruz
    Division de Genetica, Centro de Investigacion Biomedica de Occidente, CMNO, IMSS, Guadalajara, Jalisco, Mexico
    Ann Genet 43:113-6. 2000
    ..The mother had normal karyotype. The clinical and cytogenetic features of previous cases described in the literature were compared leading to a better characterization of this syndrome...
  47. ncbi An 11-year-old boy with mosaic ring chromosome 6 and dilated aortic root
    J L Ivanovich
    Department of Pediatrics, Washington University School of Medicine, St. Louis, Missouri 63110, USA
    Am J Med Genet 98:182-4. 2001
    Autosomal ring chromosomes are rare abnormalities that are inherently unstable. Children with ring chromosome 6 have a wide range of intellectual functioning and congenital anomalies...
  48. ncbi Supernumerary ring chromosomes in dermatofibrosarcoma protuberans may contain sequences from 8q11.2-qter and 17q21-qter: a combined cytogenetic and comparative genomic hybridization study
    J Nishio
    Department of Pathology, School of Medicine, Nanakuma, Jonan-ku, Fukuoka University, Fukuoka, Japan
    Cancer Genet Cytogenet 129:102-6. 2001
    ..characteristic cytogenetic features such as reciprocal t(17;22)(q22;q13) or, more commonly, supernumerary ring chromosomes containing sequences from chromosomes 17 and 22...
  49. ncbi Ring chromosome 20 epilepsy syndrome in children: electroclinical features
    P B Augustijn
    Meer en Bosch and De Cruquiushoeve, Stichting Epilepsie Instellingen Nederland, Heemstede, The Netherlands
    Neurology 57:1108-11. 2001
    ..This emphasizes the importance of full-night video-EEG in children with frontal lobe seizures and cognitive deterioration...
  50. ncbi De novo ring chromosome 6 in a child with multiple congenital anomalies
    Hadi Ahmad Ahzad
    Human Genetics Unit, Advanced Medical and Dental Institute, Universiti Sains Malaysia, Lot 29, Taman Bertam Indah, Kepala Batas, Penang, Malaysia
    Kobe J Med Sci 56:E79-84. 2010
    ..To the best of our knowledge, this is the first report of a Malay individual with ring chromosome 6, and this report adds to the collective knowledge of this rare chromosome abnormality...
  51. ncbi More severe epilepsy and cognitive impairment in the offspring of a mother with mosaicism for the ring 20 chromosome
    Eila Herrgard
    Kuopio Epilepsy Center, FIN 70211 Kuopio, Finland
    Epilepsy Res 73:122-8. 2007
    ..Cases tend to be sporadic. We elucidate the characteristics of an inherited r(20) mosaicism by describing the clinical features of three family members: a mother and her two children...
  52. ncbi Ring chromosome 20 syndrome: a link between epilepsy onset and neuropsychological impairment in three children
    Aglaia Vignoli
    Epilepsy Centre, San Paolo Hospital, University of Milan, Milan, Italy
    Epilepsia 50:2420-7. 2009
    ..Epilepsy is often the most important clinical manifestation of the syndrome, even if its appearance is not constantly precocious. Seizures are frequently drug resistant...
  53. ncbi Ring chromosomes in human neoplasias
    E Gebhart
    Institute of Human Genetics, University of Erlangen Nurnberg, Erlangen Germany
    Cytogenet Genome Res 121:149-73. 2008
    Though reported from a wide variety of human neoplasias, ring chromosomes, in general, are a rare finding in these diseases. The majority were detected by chance when tumors were screened for chromosomal aberrations...
  54. ncbi Characterization of the first supernumerary tricentric ring chromosome 1 mosaicism by conventional and molecular cytogenetic techniques
    H Tonnies
    Institute of Human Genetics, Charite, Campus Virchow Klinikum, Humboldt University, Berlin, Germany
    Cytogenet Genome Res 103:28-33. 2003
    ....
  55. ncbi A unique patient with an Ullrich-Turner syndrome variant and mosaicism for a tiny r(X) and a partial proximal duplication 1q
    A J Dawson
    Cytogenetics Laboratory, Health Sciences Centre, University of Manitoba, Winnipeg, Manitoba, Canada
    Am J Med Genet A 124:303-6. 2004
    ..However, the lower percentage of mosaicism for the dup(1) in our patient would suggest a milder influence on the clinical phenotype...
  56. ncbi Ring (Y) in two azoospermic men
    Ying Hui Lin
    Department of Obstetrics and Gynecology, National Cheng Kung University Medical College, Tainan, Taiwan
    Am J Med Genet A 128:209-13. 2004
    ..Spermatogenic defects in men with r(Y) may result from deletion of Y-linked AZFs combined with synaptic failure...
  57. ncbi Microdeletion in the SHOX 3' region associated with skeletal phenotypes of Langer mesomelic dysplasia in a 45,X/46,X,r(X) infant and Leri-Weill dyschondrosteosis in her 46,XX mother: implication for the SHOX enhancer
    Maki Fukami
    Department of Endocrinology and Metabolism, National Research Institute for Child Health and Development, Tokyo, Japan
    Am J Med Genet A 137:72-6. 2005
    ..The results, in conjunction with those reported by Flanagan et al. [2002], suggest that a cis-acting enhancer exists in the SHOX 3' region around DXYS233...
  58. ncbi Interstitial deletion 11(p11.12p11.2) and analphoid marker formation results in inherited Potocki-Shaffer syndrome
    Louise Chuang
    Department of Obstetrics and Gynecology, National Cheng Kung University Medical College and Hospital, 138 Victory Road, Tainan, Taiwan, Republic of China
    Am J Med Genet A 133:180-3. 2005
    ..12p11.2-is a newly reported site of constitutional neocentromere formation. This is also the first report describing deletion of 11p11.12-p11.2 and neocentromere formation resulting in inherited Potocki-Shaffer syndrome...
  59. ncbi Mosaic supernumerary r(8) syndrome
    S Yilmaz
    Genet Couns 16:187-90. 2005
  60. ncbi Mosaic monosomy of a neocentric ring chromosome maps brachyphalangy and growth hormone deficiency to 13q31.1-13q32.3
    David J Amor
    Murdoch Childrens Research Institute, Royal Children s Hospital, Flemington Road, Parkville 3052, Victoria, Australia
    Am J Med Genet A 133:151-7. 2005
    ..The ring chromosome appears to be prone to low-level misdivision and loss in vitro which, in vivo, must be countered by selection for the balanced karyotype because the level of mosaicism has remained stable over 13 years...
  61. ncbi Supernumerary ring chromosome 20 in a mother and her child
    M R Pinto
    Instituto de Genética Médica Dr Jacinto de Magalhães, Praça Pedro Nunes 88, 4050 466 Porto, Portugal
    Am J Med Genet A 133:193-6. 2005
    ..To our knowledge, this is the first report of a familial extra ring 20 mosaicism...
  62. ncbi Phenotype and X inactivation in 45,X/46,X,r(X) cases
    Kathleen A Leppig
    Genetic Services, Group Health Permanente, Seattle, Washington 98112, USA
    Am J Med Genet A 128:276-84. 2004
    ....
  63. ncbi Clinical and molecular cytogenetic studies in a case with partial trisomy 12p due to a de novo supernumerary ring chromosome
    M G E M Ausems
    Department of Medical Genetics, University Medical Center, Utrecht
    Genet Couns 15:405-10. 2004
    ..The girl showed developmental delay, cerebral visual impairment, obesity and mild dysmorphic features. Her clinical data at 6 months, 3 years, and 6 years of age were compared with the clinical data on other trisomy 12p patients...
  64. ncbi Mosaic ring chromosome 14 and monosomy 14 presenting with growth retardation, epilepsy, and blepharophimosis
    Jia Woei Hou
    Division of Medical Genetics, Department of Pediatrics, Chang Gung Children s Hospital, Taipei
    Chang Gung Med J 27:373-8. 2004
    b>Ring chromosomes are rare chromosomal anomalies and usually not stable in nature. Patients carrying ring chromosome have various phenotypes depending on the degree of structural rearrangement...
  65. ncbi Mosaic ring 12p and total anomalous pulmonary venous return
    Darren L Harris
    Department of Pathology, West Virginia University School of Medicine, Morgantown, West Virginia, USA
    Am J Med Genet A 131:91-3. 2004
    ..We believe ours is the first case to report the occurrence of mosaic ring 12p and its association with TAPVR...
  66. ncbi Unmasking 15q12 deletion using microarray-based comparative genomic hybridization in a mentally retarded boy with r(Y)
    Kenji Kurosawa
    Am J Med Genet A 130:322-4. 2004
  67. ncbi Transmission of ring chromosome 13 from a mother to daughter with both having a 46,XX, r(13)(p13q34) karyotype
    Jirair K Bedoyan
    Department of Genetic and Metabolic Disorders, Children s Hospital of Michigan, Detroit, Michigan 48201, USA
    Am J Med Genet A 129:316-20. 2004
    b>Ring chromosomes are thought to be the result of breakage in both arms of a chromosome, with fusion of the points of fracture and loss of the distal fragments...
  68. ncbi Supernumerary ring chromosome 8: clinical and molecular cytogenetic characterization in a case report
    Eliana Demori
    Medical Genetics Service, Children Hospital I R C C S Burlo Garofolo, Trieste, Italy
    Am J Med Genet A 130:288-94. 2004
    ..We present a detailed clinical and molecular cytogenetic characterization of this additional case in order to better define the genotype-phenotype correlation...
  69. ncbi Molecular cytogenetic characterization of a de novo supernumerary ring chromosome 7 resulting in partial trisomy, tetrasomy, and hexasomy in a child with dysmorphic signs, congenital heart defect, and developmental delay
    G von Beust
    Institute of Human Genetics, University of Goettingen, Germany
    Am J Med Genet A 137:59-64. 2005
    ..This is, to our knowledge, the first report of a partial tetrasomy to hexasomy due to a ring chromosome 7. Additionally, the ring evolution could be reconstructed according to the FISH-results...
  70. ncbi A patient with Prader-Willi syndrome and a supernumerary marker chromosome r(15)(q11.1-13p11.1)pat and maternal heterodisomy
    Marion Werner
    Department of Human Genetics, Hadassah Hebrew University Hospital and Medical School, Jerusalem, Israel
    Am J Med Genet A 129:176-9. 2004
    ..The Prader-Willi features were the result of the low mosaicism of the SMC. The evolution of the maternal heterodisomy and the SMC were two unrelated events, the occurrence of both events in the same embryo rescued it from lethality...
  71. ncbi "Ring syndrome" involving chromosome 2 confirmed by FISH analysis using chromosome-specific subtelomeric probes
    T Kosho
    Division of Medical Genetics, Saitama Children s Medical Center, Iwatsuki, Saitama 339 8551, Japan
    Genet Couns 16:65-70. 2005
    Ring syndrome" is described as those cases with complete ring chromosomes showing, independently of the chromosome involved, severe growth failure, minor dysmorphic features, and mild-to-moderate mental retardation, without major ..
  72. ncbi A case of ring chromosome 22 with deletion of the 22q13.3 region associated with agenesis of the corpus callosum, fornix and septum pellucidum
    Jose Delcan
    Unidad de Anatomía y Embriología Humana, Universidad Rey Juan Carlos, Madrid, Spain
    Prenat Diagn 24:635-7. 2004
    ..The wide range of manifestations observed in patients with this cytogenetic alteration is probably due to size differences in the deleted region...
  73. ncbi Malignant refractory epilepsy in identical twins mosaic for a supernumerary ring chromosome 19
    Amre Shahwan
    Department of Paediatric Neurology, The Children s University Hospital, Dublin, Ireland
    Epilepsia 45:997-1000. 2004
    ..The clinical picture of these twins emphasizes the importance of carrying out a karyotype study on patients with early-onset epilepsy even in the absence of dysmorphic features...
  74. ncbi Insights from genomic microarrays into structural chromosome rearrangements
    Jeroen Knijnenburg
    Laboratory for Cytochemistry and Cytometry, Department of Molecular Cell Biology, Leiden University Medical Center LUMC, Leiden, The Netherlands
    Am J Med Genet A 132:36-40. 2005
    ..the structural basis of chromosome rearrangement, including instability and mechanisms of formation of ring chromosomes. We also showed that array results might impact the recurrence risks for relatives of affected individuals...
  75. ncbi Mosaic monosomy 14: clinical features and recognizable facies
    V McConnell
    Department of Medical Genetics, Belfast City Hospital Trust, Belfast, UK
    Clin Dysmorphol 13:155-60. 2004
    ..A recognizable facial gestalt is present in children with 14q deletions or partial monosomy 14, as well as susceptibility to infection, feeding difficulties, seizures and retinal pigmentation...
  76. ncbi Ring chromosome 4 in a patient with early onset type 2 diabetes, deafness, and developmental delay
    Piers R Blackett
    Section of Diabetes and Endocrinology, Department of Pediatrics, University of Oklahoma Health Sciences Center, Oklahoma City, OK 73104, USA
    Am J Med Genet A 137:213-6. 2005
    ..The 4q breakpoint was close to the telomere. The phenotype appears different from previous patients with 4p- or r(4), which have had more extensive 4p deletion...
  77. ncbi An active ring X and haploinsufficiency of SHOX contribute to short stature, congenital anomalies, and developmental delay in a female
    Mary Shago
    Department of Pediatric Laboratory Medicine, Hospital for Sick Children, 555 University Avenue, Toronto, Ontario M5G 1X8, Canada
    Am J Med Genet 113:279-85. 2002
    ..Deletion of one copy of the SHOX gene was detected in this patient. Haploinsufficiency of this gene is known to be correlated with short stature and mesomelic limb shortening...
  78. ncbi Characterization of supernumerary rings and giant marker chromosomes in well-differentiated lipomatous tumors by a combination of G-banding, CGH, M-FISH, and chromosome- and locus-specific FISH
    F Micci
    Department of Cancer Genetics, The Norwegian Radium Hospital, Oslo, Norway
    Cytogenet Genome Res 97:13-9. 2002
    Supernumerary ring chromosomes and/or giant marker chromosomes are often seen in soft-tissue tumors of low-grade or borderline malignancy, such as well-differentiated liposarcomas or atypical lipomas...
  79. ncbi Revaluation twenty-three years later of a supernumerary derivative chromosome 9
    Catherine Yardin
    Am J Med Genet 111:213-4. 2002
  80. ncbi De novo supernumerary ring chromosome 7: first report of a non-mosaic patient and review of the literature
    G V N Velagaleti
    Departments of Pediatrics and Pathology, University of Texas Medical Branch, Galveston, TX USA
    Clin Genet 61:202-6. 2002
    ..A review of the literature identified a total of 18 cases with ring chromosomes 7 who can be classified into two groups: (1) patients with a cell line that has 47 chromosomes with a small ..
  81. ncbi Five cases of supernumerary small ring chromosomes 1: heterogeneity and genotype-phenotype correlation
    Laura Bernardini
    Ospedale Casa Sollievo della Sofferenza, San Giovanni Rotondo e Istituto CSS Mendel, Roma, Italy
    Eur J Med Genet 50:94-102. 2007
    Genetic counselling of patients with small supernumerary ring chromosomes (sSRCs) can be difficult, especially in prenatal testing, due to the complexity in establishing a karyotype-phenotype correlation...
  82. ncbi An unexpected finding in a child with neurological problems: mosaic ring chromosome 18
    Altug Koc
    Department of Medical Genetics, Faculty of Medicine, Gazi University, Ankara, Turkey
    Eur J Pediatr 167:655-9. 2008
    ..The presented case will contribute to the identification of the genotype-phenotype correlation in chromosome 18 anomalies...
  83. ncbi Cytogenetic investigation of a child with a mosaic isochromosome 18q and ring 18q
    Noelle Souraty
    Unite de Genetique Medicale, Laboratoire de Biologie Moléculaire et Cytogénétique, Faculte de Medecine, Université Saint Joseph, Beirut, Lebanon
    Eur J Med Genet 50:379-85. 2007
    ..Molecular cytogenetic investigations confirmed that it was an i(18q) and a r(18q). The hypothesis to account for this anomaly and its corresponding phenotype are discussed...
  84. ncbi Molecular cytogenetic and clinical findings in a patient with a small supernumerary r(8) mosaicism
    Daniela Bettio
    Cytogenetic Laboratory, Operative Unit of Clinical Investigations, Humanitas Clinical Institute, IRCCS, Rozzano, Milan, Italy
    Am J Med Genet A 146:247-50. 2008
  85. ncbi [Identification and characterization of marker chromosome in Turner syndrome]
    Yue Qiu Tan
    Institute of Reproduction and Stem Cell Engineering, Central South University, Changsha, China
    Zhonghua Fu Chan Ke Za Zhi 42:679-82. 2007
    ..To analyze the karyotypes of 11 cases of Turner syndrome with marker chromosome, and study the phenotypic effects resulting from the abnormal karyotype...
  86. ncbi A boy with small supernumerary marker chromosome X identified by FISH
    A Koc
    Department of Medical Genetics, Gazi University Faculty of Medicine, Ankara, Turkey
    Genet Couns 18:393-9. 2007
    ..In this report, clinical features of our patient are compared with previously reported cases and the cytogenetic and molecular cytogenetic techniques used to detect origin of marker chromosome are discussed...
  87. ncbi Ring chromosome 7 in an Indian woman
    Anupam Kaur
    Centre for Genetic Disorders, Guru Nanak Dev University, Amritsar, India
    J Intellect Dev Disabil 33:87-94. 2008
    ..Ring chromosome 7 [r(7)] is a rare cytogenetic aberration, with only 16 cases (including 3 females) reported in the literature to date. This is the first reported case of r(7) from India...
  88. ncbi Intracytoplasmic sperm injection (ICSI) with transmission of a ring(Y) chromosome and ovotesticular disorder of sex development in offspring
    Nancy B Spinner
    Division of Human Genetics, The Children s Hospital of Philadelphia, Philadelphia, Pennsylvania 19104, USA
    Am J Med Genet A 146:1828-31. 2008
    ..This report underscores the need to obtain chromosome analysis in couples with infertility who undergo assisted reproduction...
  89. ncbi Muellerian aplasia associated with ring chromosome 8p12q12 mosaicism
    Judith Loeffler
    Institut fur Medizinische Biologie und Humangenetik, Universitat Innsbruck, Austria
    Am J Med Genet A 116:290-4. 2003
    ..Chromosome microdissection and reverse painting demonstrated that this marker contained pericentric material from chromosome 8 (8p12q12). Thus, we identified a Muellerian aplasia phenotype with partial trisomy 8 mosaicism...
  90. ncbi Ring chromosome 4 and Wolf-Hirschhorn syndrome (WHS) in a child with multiple anomalies
    Sevim Balci
    Department of Clinical Genetics, Hacettepe University Faculty of Medicine, Ihsan Dogramaci Children s Hospital, Ankara, Turkey
    Am J Med Genet A 140:628-32. 2006
    ..Both maternal and paternal chromosomal analyses were normal. We compare the phenotypic appearance of our patient with the previously reported 16 cases of ring chromosome 4 in the medical literature...
  91. ncbi Ring chromosome 12 with variable phenotypic features: clinical report and review of the literature
    Ramesh C Parmar
    The Genetics Division, Department of Pediatrics, Seth G S Medical College and K E M Hospital, Parel, Mumbai 400 055, India
    Am J Med Genet A 117:275-7. 2003
    ..Examination of 200 metaphases demonstrated 2% cell line was showing 45,XX, -12. Serum lactate dehydrogenase (LDH) level was normal ruling out overlapping monosomy 12 syndrome...
  92. ncbi Class II neocentromeres: a putative common neocentromere site in band 4q21.2
    Pamela C Warburton
    Cytogenetics Department, Genetics Centre, 5th Floor Guy s Tower, London SE1 9RT, UK
    Eur J Hum Genet 11:749-53. 2003
    ..There has been one previous report of neocentromere formation in band 4q21; the observation presented here might refine a putative common neocentromeric site to sub-band 4q21.2...
  93. ncbi Supernumerary marker chromosomes 5: confirmation of a critical region and resultant phenotype
    Loredana D'Amato Sizonenko
    Northern Regional Genetic Service, Auckland District Health Board, New Zealand
    Am J Med Genet 111:19-26. 2002
    ..This brings to seven the total of reported SMCs derived from chromosome 5. The phenotype is clear, and the level of mosaicism of the marker chromosomes is contributory to the clinical severity...
  94. ncbi Small supernumerary marker chromosome derived from proximal p-arm of chromosome 2: identification by fluorescent in situ hybridization
    Ruzica Lasan Trcić
    Division of Genetics and Metabolism, Cytogenetic Laboratory, Department of Pediatrics, Zagreb University Hospital Center, Zagreb, Croatia
    Croat Med J 44:477-9. 2003
    ..This case shows that molecular cytogenetic analysis can reveal the mechanism of the formation of the marker chromosome...
  95. ncbi Characterization of a supernumerary ring chromosome 1 mosaicism in two cell systems by molecular cytogenetic techniques and review of the literature
    Holger Tonnies
    Institute of Human Genetics, Charite, Campus Virchow Klinikum, Humboldt University, Berlin, Germany
    Am J Med Genet A 121:163-7. 2003
    ....
  96. ncbi Ring chromosome 10 (p15q26) in a patient with unipolar affective disorder, multiple minor anomalies, and mental retardation
    D Concolino
    Am J Med Genet A 123:201-3. 2003
  97. ncbi The proportion of cells with functional X disomy is associated with the severity of mental retardation in mosaic ring X Turner syndrome females
    T Kubota
    Department of Medical Genetics, Shinshu University School of Medicine, Nagano, Japan
    Cytogenet Genome Res 99:276-84. 2002
    ..One of the cases with severe MR and a complete FXD pattern neither lacked the XIST gene nor had uniparental X isodisomy, and we discuss the mechanism of the failure of XCI in this case...
  98. ncbi Ring chromosomes and low-grade gene amplification in an atypical lipomatous tumor with minimal nuclear atypia
    Clelia Tiziana Storlazzi
    Department of Clinical Genetics, Lund University Hospital, 221 85 Lund, Sweden
    Int J Oncol 23:67-71. 2003
    Atypical lipomatous tumors (ALTs) are characterized by supernumerary ring chromosomes and/or giant marker chromosomes, which typically are composed of interspersed, amplified 12q-sequences, are C-band negative, lack alpha-satellite ..
  99. pmc Definition of a critical region on chromosome 18 for congenital aural atresia by arrayCGH
    Joris A Veltman
    Department of Human Genetics, University Medical Center Nijmegen, Nijmegen, The Netherlands
    Am J Hum Genet 72:1578-84. 2003
    ..to be applicable to the detection of genetic mosaicisms and, in particular, to a detailed delineation of ring chromosomes. This study clearly demonstrates the power of the arrayCGH technology in high-resolution molecular ..
  100. ncbi Three new cases with a supernumerary ring chromosome 1
    Laura Rodriguez
    Centro de Investigación sobre Anomalías Congénitas, Instituto de Salud Carlos III, Madrid, Spain
    Clin Dysmorphol 14:169-75. 2005
    ..e. 48%, 25% and 14% of the cells, respectively. Clinical signs and symptoms vary between the three cases. The results of our three cases are compared with those from the literature...
  101. ncbi SKY assessment of two karyotypes with 0-6 supernumerary marker/ring chromosomes and review of previously reported cases with two or more markers
    Kavita S Reddy
    Department of Cytogenetics, Quest Diagnostics, Inc, San Juan Capistrano, California, USA
    Am J Med Genet A 118:156-71. 2003
    ..2, and TUPLE gene that maps to 22q11.2 did not give a signal on the markers. As expected for a majority of ring chromosomes, the pan telomere probe did not hybridize to any of the markers...

Research Grants5

  1. GENETIC STUDIES OF HUMAN CELLS
    BARBARA MIGEON; Fiscal Year: 2001
    ..We have uncovered X-chromosomal deletions (small ring chromosomes) which interfere with the chromosome's ability to inactivate, and result in severe congenital abnormalities...
  2. RIBOSOMAL GENE REPLICATION DURING MAGNIFICATION
    SHARYN ENDOW; Fiscal Year: 1990
    ..A second class of mutation, the Ring magnifier (Rm) mutations, results in magnification of bb in ring chromosomes; these alleles do not magnify in the absence of Rm...
  3. Schizophrenia Predisposition in 22q11 Deletion Syndrome
    Vandana Shashi; Fiscal Year: 2005
    ..abstract_text> ..
  4. Molecular Analysis of Alagille Syndrome
    NANCY SPINNER; Fiscal Year: 2006
    ..abstract_text> ..