In the particular case of myotonic dystrophy type 1 (DM1), a multisystemic autosomal dominant disease, the formation of large non-coding CUG repeats set up long-tract hairpins able to bind muscleblind-like proteins (MBNL), which trigger the deregulation of several splicing events such as cardiac troponin T (cTNT) and insulin receptor's, among others.
Alternative splicing of human insulin receptor gene (INSR) in type I and type II skeletal muscle fibers of patients with myotonic dystrophy type 1 and type 2.
Altered splicing of transcripts, including the insulin receptor (IR) and the cardiac troponin (cTNT), is a key feature of myotonic dystrophy type I (DM1).
These findings suggest that there is no primary defect of the insulin receptor per se in terms of insulin binding and autophosphorylation in myotonic dystrophy.
Additional marker to marker recombinations in unaffected individuals are reported and support the order and orientation of the DM linkage group as pter-(INSR, LDLR,S9)-(S19,BCL3,APOC2)-(CKMM,DM)-(S22,+ ++PRKCG)-qter.