Association of the muscarinic cholinergic 2 receptor (CHRM2) gene with major depression in women

Cholinergic neurons have been implicated in depression and in the disorders of REM sleep in depression. We examined a common A-> T 1890 polymorphism in the 3′ UTR of the cholinergic muscarinic receptor 2 (CHRM2) gene. There was a significant increase in the frequency of 11 homozygotes in 126 women with major depression (43.7%) compared to 304 women without major depression (25.7%), P=.001. There was no increase in the frequency of 11 homozygotes in 52 men with depression (26.9%) compared to 278 men without depression (27.7%). Regression analysis, scoring subjects with the 11 geno-type as 1, and those with other genotypes as 0, showed that in women r² =.030, F=13.37, P=.0003. By contrast, in men r²=.00001, F=0.002, P=.96. These results are consistent with a gender-specific role of the CHRM2 gene in depression in women.