Facioscapulohumeral Muscular Dystrophy In Chinese Population Characteristics Of Alleles 4qA/4qB In 4q Subtelomere

Objective: 1.To study the frequencies of alleles and genotypes, and structure of 4qA/4qB in 4q subtelomere in Chinese population.2.To elucidate the characteristics of alleles 4qA/4qB in Chinese patients with facioscapulohumeral muscular dystrophy (FSHD) and their relationship with pathogenesis of FSHD.3.To establish the 4qA/4qB genotype-phenotype correlation in Chinese patients with FSHD and analyze the putative roles of 4qA/4qB in pathogenesis of FSHD.Method: 1. The 4q35 EcoRI/P13E-ll fragments were detected based on digestion of genomic DNA with EcoRI, EcoRI/BlnI or HindIII, and then separated by PFGE. After blotting to a Nytran membrane, the DNA was hybridized with p13E-11. After exposure, the EcoRI allele sizes were analyzed by "curve fitting" according to the MidRange PFG marker.2.The origin and size of 4q35 EcoRI/4qA and EcoRI/4qB fragments were obtained through the same methods. Comparision of the frequencies of alleles 4qA/4qB and genotypes was preformed between normal population and FSHD patients, using chi-square test. Comparision of the fragment size of 4qA and 4qB was performed by t-test.3.The 4q or 10q origin of 4qA and 4qB fragment was differentiated from hybridization bands, meanwhile the reciprocal translocation form and translocation frequency among 4qA, 4qB and 10q26 were analyzed.Then the frequency among normal population, sporadic patients and familial patients were compared by chi-square test.4.Linear regression analysis was performed to establish the correlation between the size of pathogenic fragment and 4qA/4qB genotype, as well as the relation between the onset age and pathogenic fragment size. The correlation between onset ages of FSHD patients and different 4qA/4qB genotypes was compared by t-test.