Fig. 1.
Simplified diagram of sex steroid synthesis. Steroids: PREG, pregnenolone; PROG, progesterone. Enzymes: CYP11A1, cytochrome P450 side chain cleavage; CYP17, cytochrome P450 17α-hydroxylase/C17, 20 lyase. The enzyme 3β-HSD metabolizes DHEA into AE. AE can then be converted to other steroids: 5β-A, 5β-androstanedione; 5α-A, 5α-androstanedione; E1, estrone; T, testosterone.