Nonclassical adrenal, hyperplasia due to 21-hydroxylase-deficiency: Does genotyping predict the clinical manifestation?

8 patients of 7 families with nonclassical adrenal hyperplasia (NCAH) were analysed for defects of the 21-hydroxylase-B-gene. As the defects were small or rare, complete molecular genetic diagnostic up to sequencing of this gene was necessary to detect the genotype, which then was associated with the phenotype. However, mutations in 4 alleles from 3 families are still undetectable. Thus, correct prenatal diagnosis in NCAH-families without index patient remains difficult.