A T to C mutation at position 4079 was introduced in exon 38 resulting in a leucine to proline substitution at amino acid 1360 (p.Leu1360Pro). A loxP flanked neomycin resistance cassette was inserted in intron 38 and was removed via cre-mediated recombination. This mutation is analogous to the human c.4022T>C (p.Leu1341Pro) variant causing LGMD2B. Western blot analysis of quadriceps muscle shows significantly reduced protein levels.