ABSTRACT
Objective To analyze the CYP17 gene of two sisters with combined 17-alpha-hydroxylase/17, 20-lyase deficiency, and that of their parents. Methods Genomic DNA of the four members was prepared from peripheral blood by standard methods. All the eight exons and intron/exon boundaries of CYP17 were PCR amplified and sequenced. All the hormone levels were measured by time-resolved immunofluorometric assay. Results Combined 17-?-hydroxylase/17, 20-lyase deficiency was confirmed by marked hormone change. Sequence analysis revealed that the sisters were homozygous 985delTACinsAA of CYP17, and their parents were heterozygous 985delTACinsAA. Conclusion Novel mutation of 985delTACinsAA in CYP17 was found in two sisters with 17-?-hydroxylase/17, 20-lyase deficiency. The homozygous one can induced the phenotype and the heterozygous one is a genomic marker.