[Four novel point mutations of factor IX gene detected by denaturing gradient gel electrophoresis].

OBJECTIVE

To identify factor IX gene mutations in patients with hemophilia B.

METHODS

The coding regions, splicing junction sites and part of the 5' and 3' flanking regions of factor IX gene were screened by polymerase chain reaction (PCR) and denaturing gradient gel electrophoresis (DGGE).

RESULTS

Four amplified fragments showed abnormal electrophoresis patterns, and sequencing of them demonstrated four novel point mutations including a T to G transition at nucleotide 10,380 resulting in intron 3 covering the splicing site, a A to G transition at nucleotide 30,918 resulting in a substitution of Cys for Tyr at codon 266 in exon 8, and a A to C transition at nucleotide 31,007 resulting in a substitution of Pro for Thr at codon 299 in exon 8.

CONCLUSION

Detection of mutations by PCR, DGGE and sequencing was useful not only for understanding the structure function relationship of F IX, but also for the carrier detection and prenatal diagnosis.