Diagnosis of classical steroid 21-hydroxylase deficiency using an HLA-B locus-specific DNA-probe.
The HLA-B and steroid 21-hydroxylase loci are known to be closely linked. Restriction fragment length polymorphisms seen after digestion of genomic DNA with MspI and TaqI with the HLA-B locus-specific DNA-probe, pHLA-1.1, were examined in 7 nuclear families with classical steroid 21-hydroxylase deficiency. In each family 2 polymorphic hybridizing bands (corresponding to the 2 HLA-B genes) were seen. In all families, TaqI-generated polymorphisms allowed for identification of children previously shown on clinical and biochemical criteria to be affected by 21-hydroxylase deficiency from their unaffected sibs. The results were in complete agreement with the clinical diagnoses. Among the unaffected children, carriers could be distinguished from non-carriers in all cases by TaqI polymorphisms. MspI-generated polymorphisms allowed for full identification of genotypes in 5 families. In one family, MspI-generated polymorphisms could be used to identify affected from unaffected children, but could not distinguish between carriers and non-carriers. In another family, no identification of genotypes was possible by MspI-generated polymorphisms alone. The HLA-B locus-specific DNA-probe, pHLA-1.1, can be used for diagnosis and genotyping of individuals from families with 21-hydroxylase deficiency. This technique can be used as an alternative to HLA-serotyping, or in situations where HLA-serotyping is technically difficult, for example in chorionic villus samples.
D000312:Adrenal Hyperplasia, Congenital / Q000175:diagnosis* / Q000235:genetics / Q000276:immunology; D002648:Child; D004262:DNA Restriction Enzymes; D005260:Female; D006680:HLA Antigens / Q000032:analysis*; D015235:HLA-B Antigens; D006801:Humans; D008285:Major Histocompatibility Complex; D008297:Male; D009693:Nucleic Acid Hybridization; D010375:Pedigree; D011110:Polymorphism, Genetic; D012150:Polymorphism, Restriction Fragment Length; D013250:Steroid Hydroxylases / Q000172:deficiency*
D006680:HLA Antigens; D015235:HLA-B Antigens; D013250:Steroid Hydroxylases; D004262:DNA Restriction Enzymes