NON-CLASSIC 21 HYDROXYLASE DEFICIENCY CAUSED BY NEW COMPOUND HETEROZYGOUS MUTATIONS: A CASE REPORT AND LITERATURE REVIEW

Objective To report the genetic information of a patient with non-classic 21 hydroxylase deficiency (21-OHD) for enriching the genetic database of this disease. Methods The clinical data and gene sequencing results of a patient with non-classic 21-OHD admitted to our hospital were collected. The patient’s relatives underwent high-throughput CYP21A2 gene sequencing using peripheral blood. At the same time, a literature review was performed. Results This 16-year-old female patient presented with clitoral hypertrophy, primary amenorrhea, hirsutism, acne, and growth acceleration during pre-puberty with advanced bone age. Gene testing results showed that the CYP21A2 gene had two compound heterozygous mutations: A missense mutation, c.1451G>A (p:R484Q); and a deletion mutation, deletion exon 1-3. Her relatives’ sequencing results indicated that the missense mutation c.1451G>A (p:R484Q) originated from her maternal grandfather and mother, and the deletion mutation deletion exon 1-3 inherited from her paternal grandmother and father. Conclusion We discovered a case of non-classic 21-OHD caused by new compound heterozygous gene mutations, which enriched the pathogenic mutation database of 21-OHD and could help improve clinicians’ understanding of the disease.