BDNF and androgen insensitivity syndrome: In six studies [26, 30, 33, 55, 89, 103] comprising 1241 cases (585 patients with a GG genotype and 656 without) (Fig. 3) showed patients with AIS who carried at codon 196 of the BDNF, the GA or AA genotypes were more likely to have poor outcome: OR 1.41 (1.02–1.94, p = 0.04).