Single nucleotide polymorphisms (SNPs) in the genes for estrogen receptor α (ESR1), estrogen receptor β (ESR2), matrilin 1 (MATN1), melatonin receptor 1B (MTNR1B), tryptophan hydroxylase 1(TPH1), interleukin-6 (IL-6) and matrix metalloproteinase-3 (MMP-3) have been reported to be associated with AIS predisposition [15]–[20]. This evidence concerns the gene MTNR1B and androgen insensitivity syndrome.