Comprehensive Rapid Identification of Female Carriers of DMD/BMD by lon-Pair Reversed-Phase High Performance Liquid Chromatography

Genetic typing of the intronic (CA)n loci 44, 45, 49, and 50 within the dystrophin (DMD) gene is widely used to determine carrier status for Duchenne and Becker muscular dystrophies. This is typically accomplished by electrophoresis-based methods following PCR amplification with fluoresceentlylabeled primers. We have used the unlabeled ion-pair reversed-phase high performance liquid chromatography (IP-RP-HPLC) to develop a simple and rapid method for rapid identification of female carriers of the dystrophin gene. DNA molecular size markers were efficiently used to type the 2-bp short tandem repeat (STR). In our Egyptian sample of 98 chromosomes, the most common alleleswithin the DMD gene were 200, 176, 245, and 243 bp due to STR44, 45, 49, and 50 markers, respectively. The true heterozygosity values of these markers range from 73.5 to 90.9%, and observed allele numbers range from 8 to 17 in 98 chromosomes revealing high polymorphism of the four (CA)n system of the DMD gene.