Synaptosomal-associated protein 25 (SNAP25) is an essential component for synaptic vesicle mediated release of
neurotransmitters. Deficiencies or abnormal structure or function of
SNAP25 protein, possibly arising through genetic variations in the relevant
DNA code, has been suggested to play role in the pathology of several neurobehavioural disorders including
Attention deficit Hyperactivity Disorder (
ADHD) and a number of polymorphisms in the SNAP25 gene has been studied for association with the disorder. In the present investigation, for the first time association between
ADHD and six SNAP25 polymorphisms, rs1889189, rs362569, rs362988, rs3746544, rs1051312, and rs8636 was explored in eastern Indian population. Subjects were recruited following the Diagnostic and Statistical Manual for
Mental Disorders-IV. Genomic
DNA isolated from peripheral blood leukocytes of
ADHD probands (n = 150), their parents (n = 272) and ethnically matched controls (n = 100) was used for amplifying target sites. Data obtained were subjected to population- as well as family-based analyses. While case-control analysis revealed lack of any significant difference for alleles, family-based studies revealed a mild over transmission rs3746544 'T' and rs8636 'C' alleles (P = 0.05 and 0.03 respectively). Haplotypes formed between rs362569 "T", 362988 "G", rs3746544 "T", rs1051312 "T" and rs8636 "C" in different combinations showed statistically significant transmission to
ADHD probands. Excepting rs3746544 and rs8636, all the tested sites showed very low linkage disequilibrium between them. Data obtained in this preliminary study indicates that rs3746544 'T' allele may have some role in the disease etiology in the studied Indian population.