An index case for the attenuated end of the mucopolysaccharidosis type VI clinical spectrum.

Mucopolysaccharidosis type VI (MPS VI, Maroteaux-Lamy syndrome, McKusick #253200) is a lysosomal storage disorder that is caused by a deficiency in the lysosomal exohydrolase N-acetylgalactosamine-4-sulphatase (4-sulphatase, EC 3.1.6.