Is multiple sclerosis inherited?
Although its role is unclear, genetics may play a role in multiple sclerosis. European gypsies, Eskimos and African Bantu essentially do not develop multiple sclerosis, while Native Indians of North and South America, Japanese and other Asian groups have a low incidence. The general population has less than a one-percent chance of ever contracting multiple sclerosis. The chance increases in families where a first-degree relative has the disease. Thus, a brother, sister, parent, or child of a person with multiple sclerosis stands a one-percent to three percent chance of developing multiple sclerosis. Similarly, an identical twin runs a nearly 30% chance of acquiring multiple sclerosis whereas a non-identical twin has only a 4% chance if the other twin has the disease. These statistics suggest that genetic factors play a major role in multiple sclerosis. However, other data suggest that environmental factors also play an important role.