Genetical aspects of congenital adrenal hyperplasia in the Republic of North Ossetia - Alania

Abstract

Congenital Adrenal Hyperplasia (CAH) - group of diseases based on the defect of the one of the enzymes which are involved in cortisol biosynthesis in the adrenal cortex. CAH is one of the most common inborn errors of metabolism that are transmitted as autosomal-recessive traits, which can be fatal or disabling in the case of the late diagnosis. The aim of this study is the evaluation of the efficacy of the CAH neonatal screening due to 21-hydroxylase deficiency in RNO-Alania, study of the structure and detection of the CAH frequency in the region also molecular-genetic features in the population. Retrospective analysis of medical records of the patients with CAH, diagnosed before the implementation of neonatal screening, was performed and tests results of the newborns, who were tested for CAH for 11 years, from the period January 2007 to December 2017. Studies revealed that 21-hydroxylase deficiency, which is more common in CAH, is 1:18725 among the newborns, which is considerably lower then in general in Russia (1:9500). However, high frequency of rare type of the CAH - 3 β-hydroxysteriod dehydrogenase deficiency was revealed in the ossetian population 1:22 470. In most world populations the 21- hydroxylase deficiency is dominant type and is 100 times higher then 3β-HSD. Taking into consideration that among ossetian ethic group close marriages are rare, high frequency of the detected mutation W230X in 3β-HSD gene can be explained by «founder effect».