Alpha-N-acetylgalactosaminidase deficiency, also known as Schindler disease, is an inherited disorder that can affect the development of the nervous system. People with alpha-N-acetylgalactosaminidase deficiency often have distinctive facial features that can be described as "coarse" and tooth abnormalities such as widely-spaced teeth and missing teeth (hypodontia).

Variants (also called mutations) in the NAGA gene cause alpha-N-acetylgalactosaminidase deficiency. The NAGA gene provides instructions for making the enzyme alpha-N-acetylgalactosaminidase. This enzyme works in the lysosomes, which are compartments within cells that digest and recycle materials. Alpha-N-acetylgalactosaminidase helps break down complexes called glycoproteins and glycolipids, which consist of sugar molecules attached to certain proteins and fats.

Alpha-N-acetylgalactosaminidase deficiency is very rare. Fewer than 50 individuals with this condition have been reported in the medical literature. Some cases of alpha-N-acetylgalactosaminidase deficiency likely remain undiagnosed.

This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell must have a variant to cause the disorder. The parents of an individual with an autosomal recessive condition each carry one copy of the altered gene, but they typically do not show signs and symptoms of the condition.

Published Date: March 13, 2025
Published By: National Institutes of Health