What is muscular dystrophy?Muscular Dystrophy (MD) is the name of a group of muscle disorders that are characterized by progressive weakness and wasting of the voluntary muscles that are responsible for the body movements. As muscle tissue weakens and wastes away, it is replaced by fatty and connective tissue.
What causes muscular dystrophy?Each form of muscular dystrophy is caused by an error in a specific gene associated with muscle function.
Where do the faulty genes come from?When a baby is formed, he/she receives 23 chromosomes from each parent, for a total of 46 chromosomes (23 pairs). Normally, each pair of chromosomes carries genes for the same trait. 22 pairs of the chromosomes are called autosomal chromosomes, which simply means that they are identical in both males and females. The 23rd chromosomal pair is known as the sex chromosome, and it is here that the sex of the unborn child is determined. Each female carries two X chromosomes and each males carries one X and one Y chromosome. An unborn child will receive one X chromosome from the mother and either an X or a Y from the father. If an X is received from each parent, the child will be a girl (XX). If a Y is received from the father, then the child will be a boy (XY).
Genes are found packed together on these chromosomes. Each gene has a precise location on one of them. For reasons that are only partly understood, one or more genes may become flawed or lost, and a serious disorder may result.
The type of muscular dystrophy depends on the faulty or missing genes that may be inherited. Also, the way that the disorder is inherited will vary from case to case. There are three main patterns of inheritance: autosomal dominant and autosomal recessive, which relate to transmission of traits determined by genes on the autosomal chromosomes, and X–linked recessive, which pertains to traits determined by genes found on the X chromosomes.