Nonisotopic single strand conformation analysis of the 5 alpha-reductase type 2 gene for the diagnosis of 5 alpha-reductase deficiency.
5 alpha-Reductase deficiency is a rare autosomal recessive disorder of defective virilization in karyotypic males due to reduced conversion of testosterone to dihydrotestosterone. The gene encoding the affected 5 alpha-reductase type 2 enzyme has recently been cloned, and mutations within the coding region have been discovered as the cause of this disease. We address the possibility of a rapid nonradioactive molecular genetic screening technique for initial diagnosis and report different point mutations in this gene in eight unrelated patients with clinical features of 5 alpha-reductase deficiency. For molecular genetic analysis, DNA from peripheral blood leukocytes was studied. The coding region of the 5 alpha-reductase type 2 gene was characterized by exon-specific PCR amplification, nonradioactive single strand conformation analysis, and direct sequencing. In seven patients, homozygous point mutations were identified (Leu55-Gln, delta Met157, Gly196-Ser, Arg227-Gln, Ala228-Thr, and His231-Arg). One individual was a compound heterozygote carrier of two mutations (Ile112-Asn and Gln126-Arg). We conclude that molecular genetic characterization of point mutations in the 5 alpha-reductase type 2 gene may be used as an additional valuable procedure for the diagnosis of this disorder.
Hiort
O
O
Department of Pediatrics, Medical University of Lubeck, Germany.
Sinnecker
G H
GH
Willenbring
H
H
Lehners
A
A
Zöllner
A
A
Struve
D
D
D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase / Q000172:deficiency* / Q000235:genetics*; D000595:Amino Acid Sequence; D001483:Base Sequence; D003241:Consanguinity; D004247:DNA / Q000097:blood; D006801:Humans; D007527:Isoenzymes / Q000235:genetics*; D007962:Leukocytes / Q000737:chemistry; D008297:Male; D008969:Molecular Sequence Data; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D018807:Polymorphism, Single-Stranded Conformational
D007527:Isoenzymes; D004247:DNA; D013741:3-Oxo-5-alpha-Steroid 4-Dehydrogenase