Gene Symbol: TPH2
Description: tryptophan hydroxylase 2
Alias: ADHD7, NTPH, tryptophan 5-hydroxylase 2, neuronal tryptophan hydroxylase, tryptophan 5-monooxygenase 2
Species: human
Products:     TPH2

Top Publications

  1. Gacek P, Conner T, Tennen H, Kranzler H, Covault J. Tryptophan hydroxylase 2 gene and alcohol use among college students. Addict Biol. 2008;13:440-8 pubmed publisher
    ..Tryptophan hydroxylase (TPH2) plays an important role in serotonergic neurotransmission by serving as the rate-limiting enzyme for serotonin ..
  2. Cichon S, Winge I, Mattheisen M, Georgi A, Karpushova A, Freudenberg J, et al. Brain-specific tryptophan hydroxylase 2 (TPH2): a functional Pro206Ser substitution and variation in the 5'-region are associated with bipolar affective disorder. Hum Mol Genet. 2008;17:87-97 pubmed
    ..In the brain, 5-HT production is controlled by tryptophan hydroxylase 2 (TPH2)...
  3. Furmark T, Henningsson S, Appel L, Ahs F, Linnman C, Pissiota A, et al. Genotype over-diagnosis in amygdala responsiveness: affective processing in social anxiety disorder. J Psychiatry Neurosci. 2009;34:30-40 pubmed
    ..linked polymorphic region (5-HTTLPR) and the T variant of the G-703T polymorphism in the tryptophan hydroxylase-2 (TPH2) gene have previously been associated with amygdala hyperresponsivity to negative faces in healthy controls...
  4. Zill P, Baghai T, Zwanzger P, Schule C, Eser D, Rupprecht R, et al. SNP and haplotype analysis of a novel tryptophan hydroxylase isoform (TPH2) gene provide evidence for association with major depression. Mol Psychiatry. 2004;9:1030-6 pubmed
    ..Recently, a second TPH isoform (TPH2) was identified in mice, which was exclusively present in the brain...
  5. Pereira P, Romano Silva M, Bicalho M, De Marco L, Correa H, de Campos S, et al. Association between tryptophan hydroxylase-2 gene and late-onset depression. Am J Geriatr Psychiatry. 2011;19:825-9 pubmed publisher
    The aim of this study was to examine the association between polymorphisms (SNP) in the tryptophan hydroxylase-2 (TPH2) gene and late-onset depression (LOD) in the Brazilian population...
  6. Gizatullin R, Zaboli G, Jonsson E, Asberg M, Leopardi R. The tryptophan hydroxylase (TPH) 2 gene unlike TPH-1 exhibits no association with stress-induced depression. J Affect Disord. 2008;107:175-9 pubmed
    ..Hence, the results suggest that in this particular group of stress-induced depression patients TPH-1 appears to be more relevant to MD pathogenesis than TPH-2. ..
  7. Sheehan K, Hawi Z, Gill M, Kent L. No association between TPH2 gene polymorphisms and ADHD in a UK sample. Neurosci Lett. 2007;412:105-7 pubmed
    Tryptophan Hydroxylase 2 (TPH2) is the rate-limiting enzyme in the biosynthesis of serotonin which is exclusively expressed in the brain...
  8. Zupanc T, Pregelj P, Tomori M, Komel R, Paska A. TPH2 polymorphisms and alcohol-related suicide. Neurosci Lett. 2011;490:78-81 pubmed publisher
    ..implication of polymorphisms in suicide and alcohol-related suicide, but further studies are needed to clarify the interplay among serotonergic system disfunction, suicide, alcohol dependence, impulsivity and the role of TPH2 enzyme.
  9. Walther D, Peter J, Bashammakh S, Hörtnagl H, Voits M, Fink H, et al. Synthesis of serotonin by a second tryptophan hydroxylase isoform. Science. 2003;299:76 pubmed

More Information


  1. Lin Y, Chao S, Chen T, Lai T, Chen J, Sun H. Association of functional polymorphisms of the human tryptophan hydroxylase 2 gene with risk for bipolar disorder in Han Chinese. Arch Gen Psychiatry. 2007;64:1015-24 pubmed
    The tryptophan hydroxylase 2 (TPH2) gene encodes the first (also the rate-limiting) enzyme in the serotonin biosynthetic pathway...
  2. McKinney J, Johansson S, Halmøy A, Dramsdahl M, Winge I, Knappskog P, et al. A loss-of-function mutation in tryptophan hydroxylase 2 segregating with attention-deficit/hyperactivity disorder. Mol Psychiatry. 2008;13:365-7 pubmed publisher
  3. Mokrovic G, Matosic A, Hranilovic D, Stefulj J, Novokmet M, Oreskovic D, et al. Alcohol dependence and polymorphisms of serotonin-related genes: association studies. Coll Antropol. 2008;32 Suppl 1:127-31 pubmed
    ..5HTT-LPR), monoamine oxidase A (MAOA-uVNTR) and B (MAOB-A/G) and tryptophan hydroxylase 1 (TPH1 A218C) and 2 (TPH2 G-703T) genes. An increase in the frequencies of 10-repeat allele (p = 0.010; OR = 1.73; 95% CI = 1.14-2...
  4. Zill P, Büttner A, Eisenmenger W, Moller H, Bondy B, Ackenheil M. Single nucleotide polymorphism and haplotype analysis of a novel tryptophan hydroxylase isoform (TPH2) gene in suicide victims. Biol Psychiatry. 2004;56:581-6 pubmed
    ..Recently, a second tryptophan hydroxylase isoform (TPH2) was identified in mice, which was exclusively present in the brain...
  5. Gutknecht L, Jacob C, Strobel A, Kriegebaum C, Muller J, Zeng Y, et al. Tryptophan hydroxylase-2 gene variation influences personality traits and disorders related to emotional dysregulation. Int J Neuropsychopharmacol. 2007;10:309-20 pubmed
    Variation in the tryptophan hydroxylase-2 gene (TPH2) coding for the rate-limiting enzyme of serotonin (5-HT) synthesis in the brain modulates responses of limbic circuits to emotional stimuli and has been linked to a spectrum of clinical ..
  6. Scheuch K, Lautenschlager M, Grohmann M, Stahlberg S, Kirchheiner J, Zill P, et al. Characterization of a functional promoter polymorphism of the human tryptophan hydroxylase 2 gene in serotonergic raphe neurons. Biol Psychiatry. 2007;62:1288-94 pubmed
    Tryptophan hydroxylase 2 (TPH2) is the rate-limiting enzyme in brain serotonin (5-HT) biosynthesis...
  7. Furmark T, Appel L, Henningsson S, Ahs F, Faria V, Linnman C, et al. A link between serotonin-related gene polymorphisms, amygdala activity, and placebo-induced relief from social anxiety. J Neurosci. 2008;28:13066-74 pubmed publisher
    ..transporter-linked polymorphic region (5-HTTLPR) and the G-703T polymorphism in the tryptophan hydroxylase-2 (TPH2) gene promoter...
  8. Waider J, Araragi N, Gutknecht L, Lesch K. Tryptophan hydroxylase-2 (TPH2) in disorders of cognitive control and emotion regulation: a perspective. Psychoneuroendocrinology. 2011;36:393-405 pubmed publisher
    Based on genetic variation, there is accumulating evidence that altered function of tryptophan hydroxylase-2 (TPH2), the enzyme critical for synthesis of serotonin (5-HT) in the brain, plays a role in anxiety-, aggression- and depression-..
  9. Baehne C, Ehlis A, Plichta M, Conzelmann A, Pauli P, Jacob C, et al. Tph2 gene variants modulate response control processes in adult ADHD patients and healthy individuals. Mol Psychiatry. 2009;14:1032-9 pubmed publisher
    ..In that respect, several variants of the tryptophan hydroxylase gene (TPH2), which codes for the rate-limiting enzyme in the biosynthesis of serotonin (5-HT), have been associated with ADHD...
  10. Wrzosek M, Łukaszkiewicz J, Wrzosek M, Serafin P, Jakubczyk A, Klimkiewicz A, et al. Association of polymorphisms in HTR2A, HTR1A and TPH2 genes with suicide attempts in alcohol dependence: a preliminary report. Psychiatry Res. 2011;190:149-51 pubmed publisher
    We investigated a relationship between selected polymorphisms: rs6313 in HTR2A, rs6295 in HTR1A and rs1386494 in TPH2, and suicidal behaviour in 150 alcohol-dependent patients...
  11. De Luca V, Mueller D, Tharmalingam S, King N, Kennedy J. Analysis of the novel TPH2 gene in bipolar disorder and suicidality. Mol Psychiatry. 2004;9:896-7 pubmed
  12. Ramoz N, Cai G, Reichert J, Corwin T, Kryzak L, Smith C, et al. Family-based association study of TPH1 and TPH2 polymorphisms in autism. Am J Med Genet B Neuropsychiatr Genet. 2006;141B:861-7 pubmed
    The TPH1 and TPH2 genes encode the rate-limiting enzymes that control serotonin biosynthesis, and serotonin is clearly altered in autism...
  13. Lim J, Pinsonneault J, Sadee W, Saffen D. Tryptophan hydroxylase 2 (TPH2) haplotypes predict levels of TPH2 mRNA expression in human pons. Mol Psychiatry. 2007;12:491-501 pubmed
    Tryptophan hydroxylase isoform 2 (TPH2) is expressed in serotonergic neurons in the raphe nuclei, where it catalyzes the rate-limiting step in the synthesis of the neurotransmitter serotonin...
  14. Chen C, Glatt S, Tsuang M. The tryptophan hydroxylase gene influences risk for bipolar disorder but not major depressive disorder: results of meta-analyses. Bipolar Disord. 2008;10:816-21 pubmed publisher
    ..Further replication of these findings in additional large case-control and family-based association is needed before TPH can be designated a risk gene for bipolar disorder. ..
  15. Booij L, Turecki G, Leyton M, Gravel P, Lopez de Lara C, Diksic M, et al. Tryptophan hydroxylase(2) gene polymorphisms predict brain serotonin synthesis in the orbitofrontal cortex in humans. Mol Psychiatry. 2012;17:809-17 pubmed publisher
    ..Associations in the OBFC remained statistically significant in a mixed larger sample of patients and controls. These results suggest that in humans, genetic factors might partly account for variations in serotonin synthesis in the OBFC. ..
  16. Mann J, Currier D, Murphy L, Huang Y, Galfalvy H, Brent D, et al. No association between a TPH2 promoter polymorphism and mood disorders or monoamine turnover. J Affect Disord. 2008;106:117-21 pubmed
    Tryptophan hydroxylase (TPH) is the rate-limiting enzyme in serotonin synthesis. TPH2 is a recently discovered isoform that is expressed predominantly in serotonin neurons...
  17. Breidenthal S, White D, Glatt C. Identification of genetic variants in the neuronal form of tryptophan hydroxylase (TPH2). Psychiatr Genet. 2004;14:69-72 pubmed
    We screened the complete protein coding sequence of the newly identified neuronal form of tryptophan hydroxylase (TPH2) for genetic variants...
  18. Tsai S, Hong C, Liou Y, Yu Y, Chen T, Hou S, et al. Tryptophan hydroxylase 2 gene is associated with major depression and antidepressant treatment response. Prog Neuropsychopharmacol Biol Psychiatry. 2009;33:637-41 pubmed publisher
    Tryptophan hydroxylase-2 (TPH2) is the rate-limiting biosynthetic isoenzyme for serotonin that is preferentially expressed in the brain and has been implicated in the pathogenesis of major depressive disorder (MDD) and in the mechanism of ..
  19. Shen X, Wu Y, Qian M, Wang X, Hou Z, Liu Y, et al. Tryptophan hydroxylase 2 gene is associated with major depressive disorder in a female Chinese population. J Affect Disord. 2011;133:619-24 pubmed publisher
    ..371 normal controls were recruited from local community. Patients and normal controls were genotyped for TPH2 (rs4290270 and rs7305115) variants by polymerase chain reaction. Male and female subjects were analyzed separately...
  20. Lopez V, Detera Wadleigh S, Cardona I, Kassem L, McMahon F. Nested association between genetic variation in tryptophan hydroxylase II, bipolar affective disorder, and suicide attempts. Biol Psychiatry. 2007;61:181-6 pubmed
    ..implicated in both BPAD and suicide, and the gene encoding the brain-expressed isoform of tryptophan hydroxlyase (TPH2) has been described...
  21. Bach Mizrachi H, Underwood M, Tin A, Ellis S, Mann J, Arango V. Elevated expression of tryptophan hydroxylase-2 mRNA at the neuronal level in the dorsal and median raphe nuclei of depressed suicides. Mol Psychiatry. 2008;13:507-13, 465 pubmed publisher
    ..Paradoxically, in the dorsal raphe nucleus (DRN) there are more serotonin neurons and more neuronal tryptophan hydroxylase-2 (TPH2) expression postmortem in depressed suicides...
  22. Utge S, Soronen P, Partonen T, Loukola A, Kronholm E, Pirkola S, et al. A population-based association study of candidate genes for depression and sleep disturbance. Am J Med Genet B Neuropsychiatr Genet. 2010;153B:468-476 pubmed publisher
    ..The major findings were associations of TPH2 (rs12229394) with depression accompanied by fatigue in women and CREB1 (rs11904814) with depression alone in men...
  23. Zhang X, Beaulieu J, Sotnikova T, Gainetdinov R, Caron M. Tryptophan hydroxylase-2 controls brain serotonin synthesis. Science. 2004;305:217 pubmed
    Dysregulation of brain serotonin contributes to many psychiatric disorders. Tryptophan hydroxylase-2 (Tph2), rather than Tph1, is preferentially expressed in the brain...
  24. Haghighi F, Bach Mizrachi H, Huang Y, Arango V, Shi S, Dwork A, et al. Genetic architecture of the human tryptophan hydroxylase 2 Gene: existence of neural isoforms and relevance for major depression. Mol Psychiatry. 2008;13:813-20 pubmed publisher
    ..Tryptophan hydroxylase-2 (TPH2), is the rate limiting biosynthetic isoenzyme for serotonin that is preferentially expressed in the brain and a ..
  25. Yoon H, Kim Y. TPH2 -703G/T SNP may have important effect on susceptibility to suicidal behavior in major depression. Prog Neuropsychopharmacol Biol Psychiatry. 2009;33:403-9 pubmed publisher
    ..association of serotonin 2A receptor gene -1438A/G SNP (HTR2A -1438A/G), tryptophan hydroxylase 2 gene -703G/T SNP (TPH2 -703G/T) and serotonin 1A receptor C-1019G (HTR1A C-1019G) with suicidal behavior...
  26. Goenjian A, Bailey J, Walling D, Steinberg A, Schmidt D, Dandekar U, et al. Association of TPH1, TPH2, and 5HTTLPR with PTSD and depressive symptoms. J Affect Disord. 2012;140:244-52 pubmed publisher
    To examine the potential contribution of the serotonin hydroxylase (TPH1 and TPH2) genes, and the serotonin transporter promoter polymorphism (5HTTLPR) to the unique and pleiotropic risk of PTSD symptoms and depressive symptoms...
  27. Buttenschøn H, Flint T, Foldager L, Qin P, Christoffersen S, Hansen N, et al. An association study of suicide and candidate genes in the serotonergic system. J Affect Disord. 2013;148:291-8 pubmed publisher
    ..the Serotonin Transporter (SLC6A4), Monoamine Oxidase-A (MAOA) and the Tryptophan Hydroxylase I and II (TPH1 and TPH2) genes...
  28. Delorme R, Durand C, Betancur C, Wagner M, Ruhrmann S, Grabe H, et al. No human tryptophan hydroxylase-2 gene R441H mutation in a large cohort of psychiatric patients and control subjects. Biol Psychiatry. 2006;60:202-3 pubmed
    ..Additional data by other groups should contribute to the clarification of the discrepancy between our results and those previous published. ..
  29. Van Den Bogaert A, Sleegers K, De Zutter S, Heyrman L, Norrback K, Adolfsson R, et al. Association of brain-specific tryptophan hydroxylase, TPH2, with unipolar and bipolar disorder in a Northern Swedish, isolated population. Arch Gen Psychiatry. 2006;63:1103-10 pubmed
    ..Tryptophan hydroxylase 2 (TPH2) was found to be solely expressed in the brain and therefore considered an important susceptibility gene in ..
  30. Kim Y, Lee H, Yang J, Hwang J, Yoon H. A tryptophan hydroxylase 2 gene polymorphism is associated with panic disorder. Behav Genet. 2009;39:170-5 pubmed publisher
    ..The novel brain-specific serotonin synthesizing enzyme, tryptophan hydroxylase 2 (TPH2), which represents the rate-limiting enzyme of serotonin production in the brain, may therefore be of particular ..
  31. Gizer I, Ficks C, Waldman I. Candidate gene studies of ADHD: a meta-analytic review. Hum Genet. 2009;126:51-90 pubmed publisher
    ..significant heterogeneity was observed for the associations between ADHD and DAT1, DRD4, DRD5, DBH, ADRA2A, 5HTT, TPH2, MAOA, and SNAP25, suggesting that future studies should explore potential moderators of these associations (e.g...
  32. Brown S, Peet E, Manuck S, Williamson D, Dahl R, Ferrell R, et al. A regulatory variant of the human tryptophan hydroxylase-2 gene biases amygdala reactivity. Mol Psychiatry. 2005;10:884-8, 805 pubmed
    Recent studies have indicated that a newly identified second isoform of the tryptophan hydroxylase gene (TPH2) is preferentially involved in the rate-limiting synthesis of neuronal serotonin...
  33. Zill P, Preuss U, Koller G, Bondy B, Soyka M. SNP- and haplotype analysis of the tryptophan hydroxylase 2 gene in alcohol-dependent patients and alcohol-related suicide. Neuropsychopharmacology. 2007;32:1687-94 pubmed
    ..Recent studies have indicated that a newly identified second isoform of the tryptophan hydroxylase gene (TPH2) is preferentially involved in the rate limiting synthesis of neuronal serotonin...
  34. Chen G, Vallender E, Miller G. Functional characterization of the human TPH2 5' regulatory region: untranslated region and polymorphisms modulate gene expression in vitro. Hum Genet. 2008;122:645-57 pubmed
    Tryptophan hydroxylase-2 (TPH2) is a recently identified TPH isoform responsible for neuronal serotonin (5-HT) synthesis, and TPH2 polymorphisms are associated with a range of behavioral traits and psychiatric disorders...
  35. Lopez de Lara C, Brezo J, Rouleau G, Lesage A, Dumont M, Alda M, et al. Effect of tryptophan hydroxylase-2 gene variants on suicide risk in major depression. Biol Psychiatry. 2007;62:72-80 pubmed
    ..We investigated whether variation at the tryptophan hydroxylase-2 (TPH2) gene and its 5' upstream region may predispose to suicide in major depressive disorder (MDD) and whether this ..
  36. Serretti A, Chiesa A, Porcelli S, Han C, Patkar A, Lee S, et al. Influence of TPH2 variants on diagnosis and response to treatment in patients with major depression, bipolar disorder and schizophrenia. Psychiatry Res. 2011;189:26-32 pubmed publisher aimed at exploring whether some single nucleotide polymorphisms (SNPs) within the tryptophan hydroxylase 2 gene (TPH2) could be associated with major depression (MD), bipolar disorder (BD) and schizophrenia and whether they could ..
  37. Mouri K, Hishimoto A, Fukutake M, Shiroiwa K, Asano M, Nagasaki Y, et al. TPH2 is not a susceptibility gene for suicide in Japanese population. Prog Neuropsychopharmacol Biol Psychiatry. 2009;33:1546-50 pubmed publisher
    ..The newly identified neuronal tryptophan hydroxylase isoform 2 (TPH2), the rate-limiting enzyme in serotonin synthesis, represents a prime candidate in ..
  38. Manor I, Laiba E, Eisenberg J, Meidad S, Lerer E, Israel S, et al. Association between tryptophan hydroxylase 2, performance on a continuance performance test and response to methylphenidate in ADHD participants. Am J Med Genet B Neuropsychiatr Genet. 2008;147B:1501-8 pubmed publisher
    ..this study was to examine neuropsychological mechanisms mediating the association between tryptophan hydroxylase 2 (TPH2) and attention deficit hyperactivity disorder (ADHD). A continuous performance test (T.O.V.A...
  39. Harvey M, Gagné B, Labbé M, Barden N. Polymorphisms in the neuronal isoform of tryptophan hydroxylase 2 are associated with bipolar disorder in French Canadian pedigrees. Psychiatr Genet. 2007;17:17-22 pubmed
  40. Leppanen J, Peltola M, Puura K, Mäntymaa M, Mononen N, Lehtimaki T. Serotonin and early cognitive development: variation in the tryptophan hydroxylase 2 gene is associated with visual attention in 7-month-old infants. J Child Psychol Psychiatry. 2011;52:1144-52 pubmed publisher
    Allelic variation in the promoter region of a gene that encodes tryptophan hydroxylase isoform 2 (TPH2), a rate-limiting enzyme of serotonin synthesis in the central nervous system, has been associated with variations in cognitive ..
  41. Lin Y, Ko H, Chang F, Yeh T, Sun H. Population-specific functional variant of the TPH2 gene 2755C>A polymorphism contributes risk association to major depression and anxiety in Chinese peripartum women. Arch Womens Ment Health. 2009;12:401-8 pubmed publisher
    The rate-limiting enzyme of serotonin biosynthesis, tryptophan hydroxylase 2 (TPH2), is one of the most promising candidate genes for psychiatric disorders...
  42. Walitza S, Renner T, Dempfle A, Konrad K, Wewetzer C, Halbach A, et al. Transmission disequilibrium of polymorphic variants in the tryptophan hydroxylase-2 gene in attention-deficit/hyperactivity disorder. Mol Psychiatry. 2005;10:1126-32 pubmed
    ..Here, we investigated the effect of polymorphic variants in the gene of the tryptophan hydroxylase-2 (TPH2), the rate-limiting enzyme of serotonin (5-HT) synthesis in the brain, in children and adolescents with ADHD...
  43. Kloiber S, Kohli M, Brueckl T, Ripke S, Ising M, Uhr M, et al. Variations in tryptophan hydroxylase 2 linked to decreased serotonergic activity are associated with elevated risk for metabolic syndrome in depression. Mol Psychiatry. 2010;15:736-47 pubmed publisher
    ..This led us to investigate whether variants in the gene coding for tryptophan hydroxylase 2 (TPH2), the brain-specific and rate-limiting enzyme for serotonin biosynthesis, might be predictive for an increased ..
  44. Grigoroiu Serbanescu M, Diaconu C, Herms S, Bleotu C, Vollmer J, Mühleisen T, et al. Investigation of the tryptophan hydroxylase 2 gene in bipolar I disorder in the Romanian population. Psychiatr Genet. 2008;18:240-7 pubmed publisher
    Since the discovery of the tryptophan hydroxylase 2 gene (TPH2) several studies reported the association of TPH2 genetic variation with bipolar I (BPI) disorder...
  45. Zhang X, Gainetdinov R, Beaulieu J, Sotnikova T, Burch L, Williams R, et al. Loss-of-function mutation in tryptophan hydroxylase-2 identified in unipolar major depression. Neuron. 2005;45:11-6 pubmed
    ..Identification of a loss-of-function mutation in hTPH2 suggests that defect in brain serotonin synthesis may represent an important risk factor for unipolar major depression. ..
  46. Grohmann M, Hammer P, Walther M, Paulmann N, Büttner A, Eisenmenger W, et al. Alternative splicing and extensive RNA editing of human TPH2 transcripts. PLoS ONE. 2010;5:e8956 pubmed publisher
    ..Recently, we discovered a second TPH isoform (TPH2) in vertebrates, including man, which is predominantly expressed in brain, while the previously known TPH isoform (..
  47. Perez Rodriguez M, Weinstein S, New A, Bevilacqua L, Yuan Q, Zhou Z, et al. Tryptophan-hydroxylase 2 haplotype association with borderline personality disorder and aggression in a sample of patients with personality disorders and healthy controls. J Psychiatr Res. 2010;44:1075-81 pubmed publisher
    ..Only one study has analyzed the association between the tryptophan-hydroxylase 2 (TPH2) gene and BPD...
  48. Gao J, Pan Z, Jiao Z, Li F, Zhao G, Wei Q, et al. TPH2 gene polymorphisms and major depression--a meta-analysis. PLoS ONE. 2012;7:e36721 pubmed publisher
    Tryptophan hydroxylase-2 (TPH2) is the rate-limiting enzyme in the synthetic pathway for brain serotonin and is considered key factor for maintaining normal serotonin transmission in the central neuron system (CNS)...
  49. Peters E, Slager S, McGrath P, Knowles J, Hamilton S. Investigation of serotonin-related genes in antidepressant response. Mol Psychiatry. 2004;9:879-89 pubmed
    ..SNPs and four repeat polymorphisms located in seven candidate genes (HTR1A, HTR2A, HTR2C, MAOA, SLC6A4, TPH1, and TPH2)...
  50. De Luca V, Voineskos D, Wong G, Shinkai T, Rothe C, Strauss J, et al. Promoter polymorphism of second tryptophan hydroxylase isoform (TPH2) in schizophrenia and suicidality. Psychiatry Res. 2005;134:195-8 pubmed
    Allele and haplotype frequencies of a promoter polymorphism in the gene encoding tryptophan hydroxylase (TPH2) did not differ in 83 suicidal schizophrenic patients compared with 170 non-suicidal schizophrenic patients...
  51. Garriock H, Allen J, Delgado P, Nahaz Z, Kling M, Carpenter L, et al. Lack of association of TPH2 exon XI polymorphisms with major depression and treatment resistance. Mol Psychiatry. 2005;10:976-7 pubmed
  52. Canli T, Congdon E, Gutknecht L, Constable R, Lesch K. Amygdala responsiveness is modulated by tryptophan hydroxylase-2 gene variation. J Neural Transm (Vienna). 2005;112:1479-85 pubmed
    The tryptophan hydroxylase-2 gene (TPH2) codes for the enzyme of serotonin (5-HT) synthesis in the brain and variation of TPH2 has been implicated in disorders of emotion regulation...
  53. Stefulj J, Mokrovic G, Hranilovic D, Bordukalo Niksic T, Bakula M, Kubat M, et al. Functional promoter polymorphism of the neuronal isoform of tryptophan hydroxylase (Tph2) in suicide. Psychiatry Res. 2011;186:446-7 pubmed publisher
    The association between suicide and G-703T polymorphism of the tryptophan hydroxylase 2 (TPH2), the rate-limiting enzyme in the biosynthesis of the neurotransmitter serotonin, was studied in a sample of 291 suicide victims and 280 healthy ..
  54. Walther D, Bader M. A unique central tryptophan hydroxylase isoform. Biochem Pharmacol. 2003;66:1673-80 pubmed
    ..This led us to the detection of a second TPH gene in the genome of humans, mice, and rats, called TPH2. This gene is predominantly expressed in the brain stem, while the classical TPH gene, now called TPH1, is ..
  55. Murphy K, Zhang X, Gainetdinov R, Beaulieu J, Caron M. A regulatory domain in the N terminus of tryptophan hydroxylase 2 controls enzyme expression. J Biol Chem. 2008;283:13216-24 pubmed publisher
    ..Of the two variants of tryptophan hydroxylase, tryptophan hydroxylase 2 (TPH2) is expressed predominantly in the central nervous system, whereas tryptophan hydroxylase 1 (TPH1) is expressed ..
  56. Zhang C, Li Z, Shao Y, Xie B, Du Y, Fang Y, et al. Association study of tryptophan hydroxylase-2 gene in schizophrenia and its clinical features in Chinese Han population. J Mol Neurosci. 2011;43:406-11 pubmed publisher
    ..Tryptophan hydroxylase 2 (TPH2), a newly identified isoform of tryptophan hydroxylase (the rate limiting enzyme in the biosynthesis of serotonin), ..
  57. Herrmann M, Huter T, Muller F, Mühlberger A, Pauli P, Reif A, et al. Additive effects of serotonin transporter and tryptophan hydroxylase-2 gene variation on emotional processing. Cereb Cortex. 2007;17:1160-3 pubmed
    ..reported that functional variants of both the serotonin transporter (5-HTT) and tryptophan hydroxylase-2 genes (TPH2), 2 key regulators of the serotonergic signaling pathway, modulate amygdala activation during emotional processing...
  58. Inoue H, Yamasue H, Tochigi M, Takei K, Suga M, Abe O, et al. Effect of tryptophan hydroxylase-2 gene variants on amygdalar and hippocampal volumes. Brain Res. 2010;1331:51-7 pubmed publisher
    ..Genetic variations in human TPH2, a newly identified isoform of TPH, have been shown to impact on enzymatic activity of TPH and to be associated ..
  59. Johansson S, Halmøy A, Mavroconstanti T, Jacobsen K, Landaas E, Reif A, et al. Common variants in the TPH1 and TPH2 regions are not associated with persistent ADHD in a combined sample of 1,636 adult cases and 1,923 controls from four European populations. Am J Med Genet B Neuropsychiatr Genet. 2010;153B:1008-15 pubmed publisher
    The tryptophan hydroxylase 1 and 2 (TPH1 and TPH2) genes encode the rate-limiting enzymes in the serotonin biosynthesis. Genetic variants in both genes have been implicated in several psychiatric disorders...
  60. Illi A, Setälä Soikkeli E, Viikki M, Poutanen O, Huhtala H, Mononen N, et al. 5-HTR1A, 5-HTR2A, 5-HTR6, TPH1 and TPH2 polymorphisms and major depression. Neuroreport. 2009;20:1125-8 pubmed publisher
    ..polymorphisms [HTR1A (rs6295), HTR2A (rs6313, rs6311 and rs7997012), HTR6 (rs1805054), TPH1 (rs1800532) and TPH2 (rs1386494)] with major depressive disorder and/or treatment outcome with serotonin reuptake inhibitors...
  61. Brookes K, Xu X, Chen W, Zhou K, Neale B, Lowe N, et al. The analysis of 51 genes in DSM-IV combined type attention deficit hyperactivity disorder: association signals in DRD4, DAT1 and 16 other genes. Mol Psychiatry. 2006;11:934-53 pubmed
    ..Gene-wide tests, adjusted for the number of SNPs analysed in each gene, identified associations with TPH2, ARRB2, SYP, DAT1, ADRB2, HES1, MAOA and PNMT...
  62. Harvey M, Shink E, Tremblay M, Gagne B, Raymond C, Labbe M, et al. Support for the involvement of TPH2 gene in affective disorders. Mol Psychiatry. 2004;9:980-1 pubmed
  63. Must A, Tasa G, Lang A, Vasar E, Koks S, Maron E, et al. Variation in tryptophan hydroxylase-2 gene is not associated to male completed suicide in Estonian population. Neurosci Lett. 2009;453:112-4 pubmed publisher
    ..Tryptophan hydroxylase isoform 2 (TPH2) is the rate-limiting enzyme in the biosynthetic pathway of serotonin, being expressed in serotonergic neurons of ..
  64. Mossner R, Muller Vahl K, Doring N, Stuhrmann M. Role of the novel tryptophan hydroxylase-2 gene in Tourette syndrome. Mol Psychiatry. 2007;12:617-9 pubmed
  65. Carkaci Salli N, Flanagan J, Martz M, Salli U, Walther D, Bader M, et al. Functional domains of human tryptophan hydroxylase 2 (hTPH2). J Biol Chem. 2006;281:28105-12 pubmed
    Tryptophan hydroxylase (TPH) is the rate-limiting enzyme in serotonin biosynthesis. A novel gene, termed TPH2, has recently been described...
  66. Bicalho M, Pimenta G, Neves F, Correa H, de Moraes E, De Marco L, et al. Genotyping of the G1463A (Arg441His) TPH2 polymorphism in a geriatric population of patients with major depression. Mol Psychiatry. 2006;11:799-800 pubmed
  67. Coon H, Dunn D, Lainhart J, Miller J, Hamil C, Battaglia A, et al. Possible association between autism and variants in the brain-expressed tryptophan hydroxylase gene (TPH2). Am J Med Genet B Neuropsychiatr Genet. 2005;135B:42-6 pubmed
    ..association between autism in our sample and a recently described brain-expressed tryptophan hydroxylase gene (TPH2)...
  68. Sheehan K, Lowe N, Kirley A, Mullins C, Fitzgerald M, Gill M, et al. Tryptophan hydroxylase 2 (TPH2) gene variants associated with ADHD. Mol Psychiatry. 2005;10:944-9 pubmed
    ..Originally, the TPH gene was thought to be widely expressed, but a second form of TPH, TPH2, was recently identified and the TPH2 gene was found to be solely expressed in the brain...