Frequency of Deletions and Gene Conversions in Brazilian Patients With Congenital Adrenal Hyperplasia Due To 21-Hydroxylase Deficiency

Congenital adrenal hyperplasia due to 21-hydroxylase deficiency (CAH) is an autosomal recessive disorder due to mutations in the CYP21B structural gene. These mutations can be deletions, gene conversions or point mutations. The purpose of this study is to evaluate the incidence of deletions and gene conversions in 67 patients with CAH. DNA extracted from peripheral blood leukocytes was restricted with Taq I, blotted onto nylon membranes and hybridized with a 32P radiolabeled probe. The probe is a Bam HI fragment of the CYP21B gene that contains the complete sequence of the gene(kindly provided by MI New). We analyzed the restriction fragments of 3.7 and 2.5kb(CYP21B) and 3.2 and 2.4kb (CYP21A). To differentiate gene conversion from deletions the classification proposed by Morel et al (1989) was used.Table

Table 1