Uniparental disomy unveils a novel recessive mutation in POMT2.

•A novel c.1502A>C mutation in POMT2 causes limb girdle muscular dystrophy.•This mutation leads to abnormal functional glycosylation of α-dystroglycan.•Uniparental disomy is manifested by a 15 Mb region of homozygosity on chromosome 14.•The POMT2 locus is within the region of homozygosity on chromosome 14.•The maternal recessive POMT2 mutation is unmasked by uniparental disomy.