What is hereditary ALS?

In 5–6% of all people with ALS, multiple family members are affected by ALS—this is known as “familial ALS” (FALS). The role of genetic factors is still underestimated, as genetic mutations are present in at least 10% of all patients who have no family history of ALS. ALS in which genetic mutations are detected in one of the known ALS genes is referred to as “genetic ALS.” This term is also used even when there is no history of ALS among other family members.