Duchenne muscle dystrophy

CAUSES

Duchenne muscular dystrophy(DMD) is caused by a mutation of a gene in the X chromosome and can be inherited in an X-linked recessive fashion in the family but is also often occurs in families without a known family history of the disease. The defective gene causes Duchene muscular dystrophy by not producing enough dystrophin(a protein in the muscle) or dystrophin that works.

Generally, the symptoms of Duchenne muscular dystrophy only occurs in males because males have only one X chromosome, so when the gene in the X chromosome is defective, there is no another copy of the normal gene to produce dystrophin, therefore not enough dystrophin in order for the muscles to maintain healthy. However, females have two X chromosomes, so if one of them contains a defective gene, the other X chromosome still contains a normal gene to produce enough dystrophin to prevent the symptoms from showing.

Females who have only one X chromosome with the defective gene that causes DMD are called carriers and , sometimes carriers may develop mild muscle weakness and heart muscle problems. Males who have Duchenne muscular dystrophy lose the function of their muscles progressively and which often happens in the lower limbs.

posted by Kiwi @ 12:12 AM