Chinese Han individuals with at least one rs11178997 T allele or rs120074175 A allele are susceptible to MD even in the relative absence of high-negative life events.
It was recently reported that a rare functional variant, R441H, in the human tryptophan hydroxylase-2 gene (hTPH2) could represent an important risk factor for unipolar major depression (UP) since it was originally found in 10% of UP patients (vs. 1.4% in control subjects).