Identification of homozygous and heterozygous dy2J mice by PCR

The dystrophia muscularis dy2J/dy2J mouse is an animal model for one form of human congenital muscular dystrophy. A point mutation in the gene coding for the laminin-2 alpha 2 chain leads to the expression of a truncated, partially functional protein. We developed a simple assay for the detection of the dy2J allele, which contains a new NdeI restriction site. Genomic DNA was prepared from animals of known status and amplified by PCR. The digestion of the PCR product with the restriction enzyme resulted in characteristic profiles. Then, this technique was used to identify heterozygous mice among unaffected animals of unknown status. Subsequently, the heterozygous genotype of these mice was confirmed by the birth of dystrophic offspring after mating. This technique allows the detection of the dy2J allele in heterozygous and homozygous animals at any age.