Background: Impaired synthesis of adrenal hormones because of steroid 21 - hydroxylase deficiency is one of the common inborn errors of metabolism. The disease is caused by mutations in CYP21 gene and inherited as an autosomal recessive trait.Objectives: This study aims to detect some mutations in CYP21 gene as well as study the relationship between genotype - phenotype and the carriers in patients' family. Subjects and method:43 patients with classic 21 - hydroxylase deficiency and 10 patients' parents were analysed CYP21 gene by using PCR techniques with specific primer pairs. The data was collected and analysed by EpiInfo 6.04 and other common medical statistic method. Results:Among 43 children patients of congenital adrenal hyperplasia due to 21-hydroxylase deficiency, the rate between male and female was equavalent. The most frequent mutation causing steroid 21 - hydroxylase deficiency was deletion 8bp of exon 3. Then, was splicing site mutation of intron 2. The mutation of exon 1 (Pr030Leu) was also detected. About genotype - phenotype relationship, nearly all deletions 8bp (80%) and 12 splicing mutations (87.5%) were associated with salt - wasting phenotype. Conclusion: Parents were the carriers corresponding to the autosomal recessive rule.
Adrenal Hyperplasia ; Congenital/ diagnosis ; pathology ; therapy ; Steroid 21-Hydroxylase/ diagnostic use