GM1 gangliosidosis: A genetic lipid storage disorder that is similar in certain respects to Hurler syndrome and Tay-Sachs disease but which affects both the brain and the viscera (the internal organs). GM1 gangliosidosis causes skeletal deformities and exerts severe effects on the brain and internal organs. Death usually occurs by the age of 2.
GM1 gangliosidosis is one of the classic lipid storage diseases. The gene responsible for it maps to chromosome 3. There is no treatment for the disease. It is also known as familial neurovisceral lipidosis and Landing disease (after the pioneering pediatric pathologist Ben Landing).