Figure 12. Mutations in the human 5α-reductase type 2 gene (SDR5A2) reported in patients with the syndrome of 5α-reductase deficiency. The 5α-reductase type 2 enzyme is encoded by 5 different exons and mutations have been reported in all 5 exons, as well as a complete gene deletion, small deletions of nucleotides and splice site mutations.