Duchenne muscular dystrophy--a molecular service.

Area of Science:

• Human Genetics
• Molecular Diagnostics
• Genetic Diseases

Background:

• Duchenne muscular dystrophy (DMD) is a severe genetic disorder.
• A molecular diagnostic service was established in 1987 for Southern African families affected by DMD.
• The service aimed to provide carrier detection and prenatal diagnosis.

Purpose of the Study:

• To establish and evaluate a molecular diagnostic service for Duchenne muscular dystrophy.
• To offer carrier detection and prenatal diagnostic testing to at-risk families.
• To bank DNA samples for future genetic analysis.

Main Methods:

• Collected DNA from 100 affected males and 350 relatives from 110 families.
• Performed restriction fragment length polymorphism (RFLP) analysis and deletion screening on 60 affected males and 116 at-risk females.
• Utilized various DNA probes including pERT 87-1, pERT 87-15, pXJ1.1, pXJ2.3, pXJ1.2, P20, and cDNA probes.

Main Results:

• Detected DNA deletions in 30 out of 60 affected boys.
• Determined carrier risks for 49 women using RFLP analysis.
• Offered prenatal exclusion testing for potential carriers when affected males had died.

Conclusions:

• The molecular diagnostic service successfully provided carrier detection and prenatal diagnosis for Duchenne muscular dystrophy.
• Prenatal diagnosis led to the termination of two pregnancies with affected male fetuses.
• The service played a crucial role in genetic counseling and reproductive decision-making for affected families.