Diagnosis, treatment and genetic analysis of 11β -hydroxylase deficiency caused by CYP11B gene mutation

Congenital adrenal hyperplasia (CAH) is an autosomal recessive hereditary disease, and the 11β- hydroxylase deficiency is the second most common syndrome in different types of CAH. The occurrence of 11β- hydroxylase deficiency is related to the mutation of CYP11B gene on human autosome 8. In this report, we detected the gene mutation sites of a 14-year-old patient with 11β-hydroxylase deficiency by whole exon sequencing (WES), verified the suspected mutation by Sanger sequencing, and analyzed its characteristics. Gene sequencing revealed that homozygous missense mutation of c.1226C>T appeared on the 8th exon of CYP11B1 gene, which resulted in the mutation of the encoding protein Ser409 to phenylalanine (p. Ser409Phe), affecting the binding of heme and enzyme and resulting in the loss of CYP11B1 enzyme activity and a series of clinical symptoms. This mutation has not been reported at home and abroad. This case enriches the variation spectrum of CYP11B1 gene and provides clinical data and genetic resources for further research on the pathogenesis of 11β-hydroxylase deficiency.