CYP17A1 and classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency: Although LRS-based genotyping assay can simultaneously detect variants in CYP21A2, CYP11B1, CYP17A1, HSD3B2, and StAR genes, newborn screening for 17α-OHP is mainly used to identify 21-OHD caused by variants in CYP21A2.