Depression in men is associated with more feminine finger length ratios

Variation in the influence of prenatal androgens is thought to be reflected in an individual’s finger length ratio (2D:4D). Many recent studies have examined the relationship between adult finger length ratio and traits thought to be affected by prenatal androgens. For example, Martin, Manning, and Dowrick (1999) have suggested that increased risk of clinical depression is a cost of high organizational testosterone in men. They presented data demonstrating a non-significant trend (p = 0.24) towards higher depression in men with more masculine finger length ratios. Given that women commonly show higher rates of depression than men, we suggest that depression should be associated with lower, rather than higher organizational testosterone. We tested a sample three times larger than that used by Martin et al. (1999) and found that men with more feminine finger ratios scored higher on a test for depression measured as a personality trait (p = 0.04). This result is consistent with the hypothesis that a portion of the variation in depression is due to the organizational effects of sex hormones in men.