Juvenile amyotrophic lateral sclerosis. A report of two cases in a single family.

This paper presents two juvenile cases of familial amyotrophic lateral sclerosis. They are the first and fourth child in a family with seven children from the eastern part of Finland. All seven children, as well as the parents, were examined by our group. In the first case the disease showed a rather mild course, while in the second a noticeable progression was observed even during a period of 10 months. The patients come from a rural area with a stable population and low immigration, which may favor an enrichment of certain genes and therefore support the possible hereditary basis for the disease.