Abstract
Background: Congenital adrenal hyperplasia (CAH) classical form comprises salt wasting (SW) and simple virilizing (SV) forms. This group accounts for about 75% of the affected individuals. Variation in mutation of CYP21A2 gene may cause different phenotypes.
Objectives: We reported a case of SV 21-hydroxylase deficiency that was misdiagnosed as a boy due to completely reversed external genitalia.
Methods: Allele-specific PCR for eight common mutations and dosage analysis of the CYP21A2 gene by SALSA multiplex ligation-dependent probe amplification (MLPA) were done.
Results: The molecular analysis revealed a 30 Kb homozygous deletion of CYP21A2 gene.
Conclusion: Genotype-phenotype correlation expected SW form of the disease rather than SV form hence, this discrepancy might be caused by other genes or modifier genes.