Differential expression of the “C” and “T” alleles of the 5‐HT2A receptor gene in the temporal cortex of normal individuals and schizophrenics

A genetic association between schizophrenia and a silent C/T(102) polymorphism in the 5-HT2A receptor gene (5-HT2AR) has been previously reported; however, the mechanisms underlying this association remain unknown. Here we developed an improved quantitative assay for measurements of allele ratios, which revealed that the expression of allele "C" in the temporal cortex of normal heterozygous individuals was significantly lower than the expression of allele "T" (allele "C" to allele "T" ratio of approximately 0.8, P 26 weeks) schizophrenics (n = 11) were significantly lower than in controls (P = 0.03). The data suggest that increased prevalence of allele "C" among schizophrenics may be due to intrinsically low expression of this allele, which may contribute to a deficit in 5-HT2AR expression in some schizophrenics.