Gender role/identity and sibling sex ratio in homosexual men.

Previous research has suggested that homosexual men's sibling sex ratio-the ratio of brothers to sisters collectively reported by a group of individuals-is elevated but only in samples of extremely feminine (e.g., transsexual) homosexual men. I conducted an additional test of a sibling sex ratio effect in a general sample of homosexual men (N = 237), and examined the correlation between sibling sex ratio and childhood gender identity. I found no significant effects. My discussion focuses on why little evidence of a relationship between sibling sex ratio and cross-gender behavior in childhood occurs within this general sample of homosexual men when samples selected for very feminine homosexual men have detected an elevated sibling sex ratio.