Screening for The Point Mutation R356W in a Group of Syrian Patients With Congenital Adrenocortical Hyperplasia

Abstract

Aim of the study: Congenital adrenal hyperplasia includes a group of autosomal recessive disorders that cause in 95% of cases a deficiency of the enzyme 21-hydroxylase. Screening in newborns or prenatal diagnosis effectively improves the possibility of early diagnosis and initiation of treatment, and helps revealing one of the causes of virilization in female newborns. Our research aims to determine the frequency of the R356W point mutation in a group of Syrian patients with classic and non-classic phenotypes, and the correlation between the phenotype and genotype in 21-hydroxylase deficiency.

Materials end Methods: The study was conducted on 59 not related patients. The ARMS-PCR method was used to detect the presence of the R356W mutation.

Results: The R356W mutation appeared in 34 patients, heterozygous in 31 of them (91.2%) , and homozygous in three patients (8.8%). The percentage of consanguineous marriage reached 50% in the families studied. The number of patients with the simple virilization type (SV) was 14 patients (41.2%), the number of patients with the salt wasting type (SW) reached 19 patients (55.8%), while the SW-SV type  appeared in one patient (2.9%).

Conclusion: Our results are consistent with the international results about the variability of correlation between the genotype and the phenotype, but the prevalence of this mutation in the studied group is high, that may be due to the prevalence of consanguineous marriage, which must be limited due to its health risks.