Some SNPs that have been related to hypospadias include genes involved in steroid-dependent pathways such as the AR, hydroxysteroid 17-beta dehydrogenase 3 (HSD17B3), StAR-related lipid transfer protein 3 (STARD3), steroid 5 alpha-reductase 2 (SRD5A2) [17,30,38,43–47]; oestrogen-dependent genes such as oestrogen receptor 1 and 2 (ESR1 and ESR2) and ATF3 [45,54,57,62,63,66,73]. Here, SRD5A2 is linked to hypospadias.