Autism serotonin transporter polymorphism

Keywords Dopamine transporter Norepinephrine transporter Serotonin transporter Polymorphism Attention deficit h5rperactivity disorder Parkinson s disease Addiction Anxiety Depression Autism... 

Maestrini, E., Lai, C., Marlow, A., Matthews, N., Wallace, S., Bailey, A., Cook, E., Weeks, D., Monaco, A., and International Molecular Genetics of Autism Consortium. (1999) Serotonin transporter (S-HTT) and gamma-aminobuyric acid receptor subunit beta-3 (GABRB3) gene polymorphisms are not associated with autism in the IMGSA families. Am J Med Genet (Neuropsychiatr Genet), 88 492-496. 

Yirmiya, N., Pilowsky, T., Nemanov, L., Arbelle, S., Feinsilver, T, Fried, I., Ebstein, R.P. (2001) Evidence for an association with the serotonin transporter promoter region polymorphism and autism. Am J Med Genet 105 381-386. 

Hyperserotonemia has been a consistent finding in subjects with autism, which may be due to activity of serotonin-associated platelet proteins (Hranilovic et al., 2008, 2009). Interestingly, 99% of blood serotonin is contained in platelets (Anderson et al., 1987) and studies have shown that there is an approximate 50% increase in blood-levels of serotonin in subjects with autism vs. controls (McBride et al., 1998). Hypotheses for increased serotonin include increased synthesis of serotonin by tryptophan hydroxylase (TPHl), increased uptake of serotonin into platelets via serotonin transporters (5-HTT), diminished release of serotonin from platelets via serotonin 2A receptor, and decreased breakdown of serotonin by monoamine oxidase (MAOA) (Hranilovic et al., 2008). A study by Hranilovic et al. (2008) identified polymorphisms of tryptophan hydroxylase and MAOA with increased serum serotonin levels. Similarly, haplotype analysis has shown a significant association between polymorphisms of TPHl and increased serotonin in whole blood (Cross et al., 2008). 

Huang CH, Santangelo SL (2008) Autism and serotonin transporter gene polymorphisms a systematic review and meta-analysis. Am J Med Genet B Neuropsychiatr Genet 147B 903-913 Insel TR, O Brien DJ, Leckman IF (1999) Oxytocin, vasopressin, and autism is there a connection Biol. Psychiatry 45 145-157... 

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