Myotonic dystrophy is closely linked to the gene for muscle-type creatine kinase (CKMM)

Abstract
We have studied genetic linkage between the gene for creatine kinase muscle type (CKMM) and the gene for myotonic dystrophy (DM). In a panel of 65 myotonic dystrophy families from Canada and the Netherlands, a maximum lod score (Zmax) of 22.8 at a recombination frequency (Θ) of 0.03 was obtained. Tight linkage was also demonstrated for CKMM and the gene for apolipoprotein C2 (ApoC2). This establishes CKMM as a useful marker for myotonic dystrophy.