[Clinical and genetic analysis of a patient with 17-hydroxylase/17,20-lyase deficiency].

Objective To explore the clinical and genetic characteristics of a patient with 17-hydroxylase/17,20-lyase deficiency. Methods The patient was infertile without contraception. Laboratory examination showed her chromosomal karyotype to be 46, XX. DNA sequencing was performed to detect variants of CYP17A1 gene in the patient and her family members. Results Sanger sequencing revealed that the patient has carried homozygous variant c.1486C>T in the exon 8 of the CYP17A1 gene, which resulted in substitution of arginine by cysteine (p.Arg496Cys). Her family members were all heterozygotes for the same variant. Conclusion Homozygous variant of the CYP17A1 gene c.1486C>T probably underlay the 17-hydroxylase deficiency in this patient. Above finding has enabled accurate genetic counseling and prenatal diagnosis for her family.