Known familial genetic disorder

When there is a known genetic disorder in the family, consider the following issues regarding genetic conditions:

• a previously affected pregnancy
• family members with a genetic condition, for example Cystic Fibrosis or Duchenne Muscular Dystrophy
• a family origin which may increase the risk of a genetic condition, for example thalassaemia in certain Mediterranean and Asian populations, or Tay–Sachs in Ashkenazi Jews

These families may wish to be referred for genetic counselling to their Regional Centre to discuss options.

Go to the Antenatal Referrals section for more information.

Pre-implantation genetic diagnosis

A number of genetic conditions can be tested for by pre-implantation genetic diagnosis (PGD).

PGD is available in only a few centres and only for some genetic conditions.

Conditions for which PGD can be offered include:

Autosomal dominant conditions:

• Huntington’s disease
• Myotonic dystrophy
• Marfan’s syndrome

Autosomal recessive conditions:

• Cystic fibrosis
• Spinal muscular atrophy
• Tay Sachs

X-linked inheritance:

• Duchenne and Becker’s muscular dystrophy
• Haemophilia
• Fragile X syndrome

Chromosomal conditions:

• Aneuploidy (unequal number of chromosomes)
• known translocations