Molecular diagnosis of Duchene Muscular dystrophy

Abstract

Dystrophinopathies are the most common forms of muscular dystrophy in childhood, characterize by a progressive muscle weakness. Mutations in the DMD gene result in Duchenne Muscular Dystrophy (DMD) or Becker Muscular Dystrophy (BMD), inherited in X-linked recessive mode with a frequency of 1 in 3500 live born males. The present retrospective study aims to describe the mutation spectrum of DMD gene observed in 19 boys with muscular dystrophy without any clinical or familial information addressed to our laboratory between 2016 and 2020. Mutation analysis was performed by PCR multiplex using a primer set of Chamberlain and Beggs. DNA was extracted from peripheral blood and PCR products were separated on 1% agarose gel and detected in U.V light after ethidium bromide staining. The DMD gene is the largest human gene (2.4Mb) on Xp2. It consists of 79 exons encoding for dystrophin. Deletions were observed in 60% of patients, especially in the exons 3–7 and 44–55. To discern between the DMD and DMS diseases we can use a clinical approach or immunohistochemistry techniques. However, the protein-based strategy followed by molecular analysis is probably the most efficient way to approach diagnosis and to propose a correct genetic counselling. 
 Keywords: Dystrophinopathies, Polymerase chain reaction, Duchene Muscular Dystrophy, Becker Muscular Dystrophy.