Clinical and Molecular Characterization of a Cohort of 161 Unrelated Women with Nonclassical Congenital Adrenal Hyperplasia Due to 21-Hydroxylase Deficiency and 330 Family Members

The study of family members underlines the variable expression of NC-CAH even within a family, suggesting that modifier factors may modulate phenotype expression. Post-ACTH 21dF cannot reliably detect heterozygous subjects. Considering the high frequency of heterozygotes in the general population, it is essential to genotype the partner(s) of the patients with one severe mutation to offer genetic counseling.