What causes GM1 gangliosidosis ?
What causes GM1 gangliosidosis? All three types of GM1 gangliosidosis are caused by mutations (changes) in the GLB1 gene. This gene gives the body instructions to make an enzyme called beta-galactosidase (-galactosidase), which plays an important role in the brain. The enzyme resides in compartments within cells called lysosomes, where it helps break down certain molecules, including a substance called GM1 ganglioside. GM1 ganglioside is important for nerve cell function in the brain. Mutations in the GLB1 gene may lower or eliminate the activity of the -galactosidase enzyme, keeping GM1 ganglioside from being broken down. As a result, it accumulates to toxic levels in tissues and organs, particularly in the brain. This accumulation leads to the destruction of nerve cells, causing the features of the condition. In general, people with higher enzyme activity levels usually have milder features than those with lower activity levels.