Isang napakabihirang kakulangan sa enzyme (N-acetyl-alpha-D-galactosaminidase) na maaaring mangyari sa tatlong anyo: type I (infantile-onset neuroaxonal dystrophy), type II o Kanzaki disease (adult-onset) at type III (mild or moderate anyo). Tingnan din ang N-acetyl-alpha-D-galactosaminidase