Table 1.

Various types of MPS; reproduced with permission from Braunlin et al. [5], who compiled data from Neufeld et al. [2] and Valayannopoulos et al. [6].

MPS Type (Eponym)	Incidence per 105 Live Births; Inheritance Pattern	Typical Age at Diagnosis	Typical Life Expectancy If Untreated	Enzyme Deficiency	GAG
MPS I Hurler (H) MPS I Hurler–Scheie (H-S) MPS I Scheie (S)	0.11–1.67; AR	H: <1 year H-S: 3–8 years S: 10–20 years	H: death in childhood H-S: death in teens or early adulthood S: normal to slightly reduced lifespan	α-L-iduronidase	DS, HS
MPS II (Hunter)	0.1–1.07; XR	1–2 years when rapidly progressing	rapidly progressing: death < 15 years slowly progressing: death in adulthood	iduronate-2-sulfatase	DS, HS
MPS III (Sanfilippo) A-B-C-D	0.39–1.89; AR	4–6 years	death in puberty or early adulthood	heparan sulfamidase (A) N-acetyl-α-D-glucosaminidase (B) acetyl-CoA-α-glucosaminidase N-acetyltransferase (C) N-acetylglucosamine-6-sulfatase (D)	HS
MPS IV (Morquio) A-B	0.15–0.47; AR	1–3 years	death in childhood- middle age	N-acetylgalactosamine-6-sulfatase (A) β-galactosidase (B)	CS, KS (A) KS (B)
MPS VI (Maroteaux-Lamy)	0–0.38; AR	rapidly progressing: 1–9 years slowly progressing: >5 years	rapidly progressing: death in 2nd–3rd decade slowly progressing: death in 4–5th decade	N-acetylgalactosamine-4-sulfatase	DS
tblMPS VII (Sly)	0–0.29; AR	neonatal to adulthood	death in infancy- 4th decade **	β-D-glucuronidase	CS, DS, HS
MPS IX (Natowicz) *	unknown	adolescence	unknown	hyaluronidase	CS

AR—autosomal recessive, CS—chondroitin sulphate, DS—dermatan sulphate, GAG—glycosaminoglycan, H—Hurler syndrome, HS—heparan sulphate, H-S—Hurler–Scheie syndrome, KS—keratan sulphate, S—Scheie syndrome, XR—X-linked recessive. * Only 1 patient reported in literature (Natowicz et al. 1996); ** death can occur in utero with hydrops fetalis.