Approaching genetic testing and counselling for families with a history of Duchenne Muscular Dystrophy (DMD) requires a structured, informed, and sensitive process. First, genetic counselling should be provided by healthcare professionals with appropriate training in genetics, ideally in a specialist genetic clinic setting, to ensure families understand the implications of testing, including the meaning of positive, negative, or uncertain results and the likely timescale for receiving results NICE CG164.
Testing should ideally begin with an affected family member to identify the specific mutation in the dystrophin gene, which causes DMD, as this mutation finding guides subsequent predictive testing in relatives NICE CG164. This approach maximizes the informativeness and clinical utility of the genetic test.
Pre-test counselling should include at least two sessions to discuss the potential risks, benefits, and limitations of genetic testing, including the possibility of variants of uncertain significance or no mutation being found, and the implications for the individual and their family NICE CG164.
Carrier testing is particularly important for female relatives because DMD is an X-linked recessive disorder; identifying carriers can inform reproductive choices and early interventions [Frazer et al., 2013].
Families should be informed about the inheritance pattern, carrier probabilities, and options for prenatal or preimplantation genetic diagnosis if they are planning pregnancies, as well as the availability of ongoing support and review in specialist genetic services NICE CG164 Frazer et al. 2013.
Genetic counselling should also address the psychosocial impact of a DMD diagnosis or carrier status, providing opportunities for families to discuss concerns and receive tailored information about disease progression, management options, and implications for living independently [Frazer et al., 2013].
Referral pathways should be clear: primary care providers should refer families with a history suggestive of DMD to specialist genetic clinics for comprehensive assessment, testing, and counselling NICE CG164.
In summary, the approach integrates thorough pre-test counselling, mutation identification in affected individuals, targeted carrier testing, and ongoing support, all delivered by trained genetics professionals to ensure informed decision-making and optimal family care.
Key References
- CG164 - Familial breast cancer: classification, care and managing breast cancer and related risks in people with a family history of breast cancer
- NG241 - Ovarian cancer: identifying and managing familial and genetic risk
- NG78 - Cystic fibrosis: diagnosis and management
- (Frazer et al., 2013): The genetics and implications of neuromuscular diseases in pregnancy.