[Analysis of CYP17A1 gene variants in 5 patients with 17-hydroxylase deficiency]

To identify pathogenic variants in 5 sporadic patients and two Chinese pedigrees affected with 17-hydroxylase deficiency (17-OHD).

Peripheral blood samples were collected with informed consent. Variants of CYP17A1 gene were screened by PCR and Sanger sequencing. Suspected mutations were validated in other members of the pedigrees.

Gene sequencing has identified a homozygous c.985_987delTACinsAA (Y329Kfs) mutation in exon 6 of the CYP17A1 gene in 4 patients and the sister of case 3. Case 1 was found to harbor compound heterozygous mutations c.1459_1467del9 (p.D487_F489del) and c.1244-3C>A. The parents and brother of cases 2 and 5 were heterozygous carriers of a c.985_987delTACinsAA(Y329Kfs) mutation.

Mutations of the CYP17A1 gene probably underlie the pathogenesis of 17-OHD, for which c.985_987delTACinsAA(Y329Kfs) is the most common. The c.1244-3C>A is a novel mutation. Above results have facilitated genetic counseling for the affected families.