Mutation of 3β-hydroxysteroid dehydrogenase (3β-HSD) at the 3'-untranslated region is associated with adrenocortical insufficiency.

In the present study, we report the mutation of the 3β-hydroxysteroid dehydrogenase (3β-HSD) gene in a family suffering from adrenocortical insufficiency. The index patient was clinically diagnosed with adrenocortical insufficiency. Peripheral venous blood (5 ml) was collected from the proband and 5 members of his family, and genomic DNA was extracted. Exons 1, 2, 3 and 4 of the 3β-HSD gene and their flanking sequences were amplified by polymerase chain reaction (PCR). Some of the family members were examined by amplifying only exon 4. The PCR products were then purified and sequenced. The C to T homozygous mutation at nucleotide 1088 and C to G homozygous mutation at nucleotide 1132 within exon 4 of the 3β-HSD gene were found in the family members with abnormal phenotype. In the family members with normal phenotype, heterozygous mutations at the sites mentioned above were identified in the parents and Aunt 1, but not in Aunt 2 of the proband. In conclusion, a family with 3β-HSD deficiency was identified in the present study. The cause of the disease in the studied family appears to be two novel homozygous mutations in the 3β-HSD gene.