ABSTRACT
Infantile GM1 or generalized gangliosidosis is a lysosomal storage disease in which GM1 ganglioside (Figure 91.1, p. 610) accumulates in the brain and viscera [1-5]. The resultant cerebral degenerative disease is a devastating one, and affected patients usually die before 2 years-of-age. This was the first of the GM1 gangliosidoses to be described [5], and it is the most common. It has also been referred to as type 1, but as increasing genetically determined variation becomes evident, it is less appropriate to number these disorders. A spectrum of considerable differences in phenotype appears to reflect different degrees of residual enzyme activity resulting from different mutations. It has been practical clinically to consider the GM1 gangliosidosis broadly as infantile, juvenile, or adult.
