Cloning And Application Of Dystrophin Gene Deletion Junctions

Background and ObjectivePseudohypertrophic muscular dystrophy (PMD) is a kind of lethal X-chain recessive inherited disease. The etiological factor is mainly due to gene mutation of Xp21 which induce the structural and functional abnormality of a kind of cell skeleton protein: dystrophin. According to the extent of structural change and functional incapacitation of dystrophin, PMD can be divided into two types: Duchenne muscular dystrophy (DMD) and Becker muscular dystrophy (BMD). DMD is more frequent, with the incidence about 1/3500 viable birth male infant.Spanning over 2500 kb, dystrophin gene is the largest human gene that people have found up to now. It has high mutation rate and multiple mutation forms. Dystrophin gene mutation give priority to large gene fragment deletion which accounts for 55-65% in all the mutants and is the main cause of DMD/BMD. The mechanism of dystrophion gene deletion is still unclear. Now there are two main approaches to study it: one is studying the distribution of deletion breakpoints, the other is studying the sequence features of deletion junctions.Analyzing the sequence features of dystrophion gene deletion junctions needs cloning and sequencing the deletion junctions. However, dystrophin gene is very large, and the methods of cloning deletion junctions is complicated all the while, so the present sequence data of them are scarce. There are only fifties cases of sequence data of deletion junctions in literatures at home and abroad up to now. To explain the mechanism of dystrophion gene deletion with such limited data is undoubtedly...