Heterozygotes and cryptic patients in families of patients with congenital adrenal hyperplasia (21-hydroxylase deficiency). HLA and glyoxalase I typing and hormonal studies.

In a group of 18 unrelated Danish children with 21-hydroxylase deficiency (21-OH def.), human leukocyte antigen (HLA) typing revealed a significant increase of Bw47 and a significant decrease of B8. HLA studies of the families of 14 probands predicted among the siblings 11 heterozygote carriers and 3 genetically unaffected. Glyoxalase studies showed a recombination fraction of 8%. ACTH-stimulated 17-OH progesterone is the only hormone value useful in the discrimination between heterozygotes and normals. Two families are described in detail. In one family, one of two HLA-identical brothers had classical virilizing congenital adrenal hyperplasia (CAH), while the other was a normal boy without 21-OH def. In another family with 3 girls, one had classical, salt-wasting CAH, one had "late onset' CAH, and the third sister and the father shared the HLA-B14 antigen and were shown to have "cryptic' 21-OH def.