As a result, screening can identify many previously undiagnosed patients.

Mortality and morbidity are increased in undiagnosed patients.

We searched for new mutations in the DMD gene in a cohort of previously undiagnosed patients who had been referred in the period 1985-1995.

Undiagnosed patients were investigated using either massively parallel sequencing of a panel of neuromuscular disease genes panel, or whole exome sequencing.