Prenatal Diagnosis of Menkes Disease
Menkes disease is an X-linked recessive disorder of cellular copper transport. Affected males suffer neurodegeneration and death typically by the age of three years. Mothers of affected boys endure the heavy burden of caring for their sick child, coping with the loss of a child, guilt at having passed on the faulty gene, and anxiety over the risk of recurrence. Pregnant women with a family history of Menkes disease often choose to terminate the pregnancy if the pregnancy is shown to be affected. Such a choice is usually based on their own past traumatic experience with their son, brother or other family member.
Two cases are discussed where the prenatal investigation for Menkes disease was required. In the first case, the molecular diagnosis was yet to be established within the index case, and therefore copper efflux studies on chorionic villous cells were required to distinguish between an affected and unaffected male pregnancy. Copper efflux studies require the sampling and handling of fetal tissue in a copper-free environment in order not to contaminate the cells. In the second case, a molecular diagnosis had been established within the index case, allowing the pregnant woman to be identified as a carrier and appropriate testing of the pregnancy to be carried out.
The two cases highlight and contrast the methods available for the prenatal diagnosis of Menkes disease. A protocol outlining the measures required for the prenatal diagnosis of Menkes is proposed.