Analysis ofScottish Duchenne andBecker muscular dystrophy families withdystrophin cDNA probes

One hundredandthirty-two Scottish families, representing themajority ofcurrently knowncases inthiscountrywithatleast one living subject affected byDMD (110) orBMD (22), were studied witha series ofcDNA probesexcluding the3' region ofthegene (probes 10-14). Usingmainly HindIII digested DNA fromaffected males, 89 patients showeddeletions whichranged from1 to 32HindIII fragments insize. Two patients were alsodetected with exon duplications. Abnormalities were foundtobeparticularly concentrated inthe area ofprobecDNA 8,with56patients being deleted foratleast one ofthefragments detected by thisprobe.A secondsmaller concentration of deletions was foundwithprobe1-2awhichshowed 16deletions andtwoduplications. Theendpoints of cDNA deletions or duplications were determined with amaximumvariability ofone HindIII fragment in83patients, whiletheremaining eight patients hadasingle deletion endpoint defined. Thedeletions foundintwoofour patients appeartoconflict with thepreviously stated exon order atthe5'endofthe gene.Although no specific deletion patterns were apparent forDMD, thedeletions foundin13ofthe BMD patients allincluded themost proximal (10kb)fragment detected byprobe8.