Duchenne and Becker muscular dystrophy

Keywords: Duchenne/Becker muscular dystrophy

Specimen:

10 mL blood in EDTA tube.

Method:

Multiplex PCR or MLPA analysis to detect a deletion in the dystrophin gene.

Application:

Used in conjunction with creatine kinase in the diagnosis of Duchenne/Becker muscular dystrophy and in identifying female carriers.

Prenatal diagnosis for Duchenne muscular dystrophy may be available if the mother has been shown to be a carrier.

Interpretation:

Deletions within the dystrophin gene account for approximately 65% of cases of Duchenne/Becker muscular dystrophy in boys.

These deletions can usually be identified in female carriers.

The identification of a deletion in the dystrophin gene in a symptomatic male is diagnostic of Duchenne/Becker muscular dystrophy.

The identification of a deletion in one dystrophin gene in a female is diagnostic of the carrier status.

Molecular genetic studies may be indicated in other family members. The absence of a deletion does not exclude the diagnosis and family studies may clarify a woman’s carrier status.

Reference:

Laing NG et al. Med J Aust 1991; 154: 14-18.