Table 1.

Classification of mucopolysaccharidoses.

MPS	Name	Increased GAGs	Inheritance	Enzyme deficiency	Gene location
I	Hurler, Hurler-Scheie or Scheie	HS + DS	autosomal recessive	α-duronidase	4p16.3
II	Hunter	HS + DS	X-linked recessive	Iduronate sulfatase	Xq28
III A	Sanfilippo A	HS	autosomal recessive	Heparan-N-sulfatase	17q25.3
III B	Sanfilippo B	HS	autosomal recessive	α-N-acetylglucosaminidase	17q21.1
III C	Sanfilippo C	HS	autosomal recessive	AcetylCoA α- glucosamine acetyltransferase	14p21
III D	Sanfilippo D	HS	autosomal recessive	N-acetylglucosamine 6-sulfatase	12q14
IV A	Morquio A	KS	autosomal recessive	Galactosamine-6-sulfate sulfatase	16q24.3
IV B	Morquio B	KS	autosomal recessive	α-galactosidase	3p21.3
(V)	Scheie syndrome, initially proposed as type V, was recognized to be the attenuated end of the MPS I spectrum
VI	Maroteaus-Lamy	DS	autosomal recessive	N-acetylgalactamine 4-sulfatase	5q11–q13
VII	Sly	HS + DS	autosomal recessive	α-glucuronidase	7q21.11
(VIII)	An enzyme defect was found and proposed as MPS VIII, but shortly thereafter recognized as a laboratory pitfall; the proposal was with-drawn
IX	Natowicz	Hyaluronan	autosomal recessive	Hyaluronidase 1	3p21.3