Late-Onset Dystrophinopathy.

Dystrophinopathy is a spectrum of muscular dystrophies resulting from absolute to relative deficiency of dystrophin - a protein essential for muscle fiber integrity. This includes a severe form called Duchenne muscular dystrophy, a mild form called Becker muscular dystrophy, and intermediate muscular dystrophy. Becker muscular dystrophy relates to late-onset and slow progression muscle dystrophy caused by deletions or duplications in the dystrophin gene. Individuals with this type of tardive slow progression have a life expectancy of 60 years. A patient in his late 40s presented this disease with duplication of exon 2 in the dystrophin gene.