mdx, mdx3cv, and mdx4cv mice are among the most commonly used models for the study of Duchenne muscular dystrophy. Their disease is caused by point mutations in the dystrophin gene. Despite widespread use of these models, genotyping has not always been straightforward. Current methods require multiple polymerase chain reactions (PCRs), post‐PCR manipulations, and/or special equipment/reagents. Herein we report a simple, robust PCR genotyping method based on primer competition. This approach could also be applied in genotyping other point‐mutation models. Muscle Nerve , 2010