DMD and neuromuscular disease caused by qualitative or quantitative defects of dystrophin: Also, for a male patient with learning difficulties, the DMD gene variant may be responsible as intellectual disability or cognitive impairment has been reported in a proportion of males with dystrophinopathy, particularly when the pathogenic variant is towards the 3′ end of the gene (exon 45 or beyond; likely due to impact on short dystrophin isoforms expressed in the brain) [92, 93].