Genome vikings

Ethical issues in molecular screening for heterozygous familial hypercholesterolemia: the complexity of dealing with genetic susceptibility to coronary artery disease

Familial hypercholesterolemia (FH) is one of the most common inherited metabolic diseases, and is associated with an increased cardiovascular risk. The diagnosis of FH is based on clinical criteria, but molecular DNA testing is available, and has proven to be helpful in risk assessment. In addition, new technologies could be applied to FH, such as high-density DNA probe arrays and gene therapy. The use of genetic information, however, raises specific ethical concerns which indicate that DNA testing for FH should not be performed blindly. Before consenting to molecular testing, an individual must really understand FH, what risks it involves for himself as well as his family and community, and what the treatment entails. Since the cardiovascular risk of FH patients is affected by other susceptibility genes and environmental factors, an individual should be able to assess the impact of this additional risk on his health outcome. In this regard, the ethical issues raised by a simple trait such as FH may help define a community genetic approach for a complex trait such as coronary artery disease.

Ethnic variation in the mitochondrial targeting sequence polymorphism of MnSOD

In contrast to CuZn superoxide dismutase (SOD), only a very limited number of mutations have been described in MnSOD. One interesting example is a polymorphism (Ala-9Val) in the mitochondrial targeting sequence of this radical-scavenging enzyme. We have studied the Ala-9Val polymorphism in various ethnic groups by means of the oligonucleotide ligation assay. There were significant variations in this unique polymorphism between three different language groups: Baltic (Lithuanians), Finnic (Finns and Saamis) and Germanic (Swedes). The Ala frequency in an Asiatic population (Chinese) was significantly lower than in most European populations. This polymorphism may affect the mitochondrial targeting rate of MnSOD which may result in mitochondrial damage with implication in various late-onset neurological diseases.