Ethics of Screening for Huntington's Disease

In 1872, George Huntington wrote about a disease that he and his family was suffering from. Symptoms included slurred speech, involuntary or slowed movement, and compulsive emotions and feelings. Today, it is known that this disease is a genetic disease affecting the brain, caused by the mutation of chromosome number 4, in which the codon CAG repeats over 40 times, contrary to the normal 10 to 26 times. Though it is unknown as to why this repetition causes such effect on the brain, scientists have devised methods in which it would be possible for individuals to test for the disease through genetic screening. Though genetic screening could have its side effects, it is currently the best way to take preventive measures for individuals carrying the mutation to not pass on to future generations as well as provide other personal aspects that would benefit the individual the most. Huntington’s disease is a familial disease that is passed down through generations. Out of all cases of HD, 97% of the disease is contracted from parents, and only the small 3% show independent mutation. Moreover, HD is inherited as a dominant trait, meaning a single copy of the mutation is enough to affect offspring. It is therefore vital that couples on high risk of carrying the disease take preventive measures to ascertain the existence of the mutation in their genes for future generations to not pass down the disease further. Methods of genetic screening is largely divided into three – prenatal, predictive and carrier testing. Prenatal testing is done on the fetus in the early stages of pregnancy, whereas predictive and carrier testing is performed on any individual at high risk for having HD. Prenatal testing is usually not recommended for most pregnant mothers, as it carries a high risk of damaging the fetus. Predictive and carrier testing, on the other hand, are harmless methods that determine the existence of the mutation, and thus shows its effectiveness. If couples and individuals