Welcome to DMD & BMD website

Introduction

Muscular Dystrophy (MD) is a group of hereditary muscle diseases which result in exhaustion of body muscles that help movement of an individual. Deficiency in muscle proteins causes progressive skeletal muscle weakness in MD patients which ultimately results in the death of muscle cells and tissue.

There are different types of MDs. However, in this website we are going to give information on the two most common MDs which are Duchenne and Becker muscular dystrophies (DMD & BMD).

DMD is the most severe form of muscular dystrophy, where dystrophin protein is missing. BMD, however, is a milder form of muscular dystrophy where dystrophin is present, but is abnormal.

What is Duchenne Muscular Dystrophy (DMD)?

It is one of more than 20 types of muscular dystrophy. All the muscular dystrophies are due to faulty genes that have been passed on to the children from their parents. The parent (mother) may not be affected by DMD herself, and be completely normal (healthy). However, in order to have a DMD affected boy, mother must carry the faulty gene and pass it on to her son. Unless, a spontaneous mutation (change in the gene) in boy’s DNA has given rise to the faulty gene.

Individuals that are affected by DMD show a progressive muscle weakness as a result of muscle cell/ tissue break down and gradual loss.

DMD is only affected by boys (with very rare exceptions). The fault in this gene results in a deficiency of a single important protein in muscle fibres called dystrophin.

DMD is named after the French scientist, Dr Duchenne de Boulogne, in the mid-19th century who was one of the first people to study the muscular dystrophy.

What is Becker Muscular Dystrophy (BMD)?

BMD is a much milder form of the DMD. Unlike DMD, dystrophin protein is not missing in BMD but it is not normal either. As a result of this, the effects of this condition develop slowly (slower than DMD). In BMD, a milder defect in dystrophin gene leads to formation of smaller dystrophin molecules (or occasionally larger) or less abundant than normal. When dystrophin protein is abnormal the gradual break down of muscle fibres takes place, where muscles slowly become weaker and weaker. The mentioned dystrophin molecules abnormalities in muscle provide a very efficient way to diagnose and differentiate between BMD and other types of muscular dystrophy. 

Like DMD, Becker muscular dystrophy affects only males.

Typical characterisitics of muscular dystrophy disorders.

Taken from: https://www.dinf.ne.jp/doc/english/global/david/dwe002/dwe002g/dwe00212g01.gif