title: Incidence and prevalence of mucopolysaccharidosis type 1 in the Irish republic.
abstract: Mucopolysaccharidosis type 1 (MPS1) is an autosomal recessive disorder with severe, moderate and mild phenotypes: Hurler, Hurler-Scheie and Scheie syndromes. We estimated incidence (2001-2006) and prevalence (2002 census) of MPS1 in the Irish Republic (ROI) using population data, database and chart review of all live MPS1 patients attending two specialised centres. Patient genotypes, ethnicity, province of origin, age at diagnosis and presenting features were recorded. Thirty-one patients (14 females, 17 males) were alive, 27 of whom were <15 years. Twenty-six patients had Hurler syndrome, four had Hurler-Scheie and one had Scheie syndrome. The birth incidence was 1 in 26 206 births with a carrier frequency of 1 in 81. Of note, 19/26 (73%) Hurler patients were Irish Travellers. Amongst Irish Travellers the incidence was 1 in 371 with a carrier frequency of 1 in 10. This is the highest recorded incidence worldwide. Given the morbidity and mortality associated with delayed treatment we recommend targeted newborn screening for this population.
authors.affiliation: National Centre for Inherited Metabolic Disorders, Childrens University Hospital, Dublin, Republic of Ireland.
authors.forename: A M
authors.initials: AM
authors.lastname: Murphy
authors.forename: D
authors.initials: D
authors.lastname: Lambert
authors.forename: E P
authors.initials: EP
authors.lastname: Treacy
authors.forename: A
authors.initials: A
authors.lastname: O'Meara
authors.forename: S A
authors.initials: SA
authors.lastname: Lynch
mesh_terms: D017668:Age of Onset; D002648:Child; D002675:Child, Preschool; D005260:Female; D018380:Hematopoietic Stem Cell Transplantation / Q000379:methods*; D006801:Humans; D007068:Iduronidase / Q000627:therapeutic use*; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D007494:Ireland / Q000453:epidemiology; D008297:Male; D008059:Mucopolysaccharidosis I / Q000201:enzymology / Q000453:epidemiology* / Q000628:therapy; D015997:Neonatal Screening; D010641:Phenotype; D015995:Prevalence; D012042:Registries / Q000706:statistics & numerical data*; D012189:Retrospective Studies; D012720:Severity of Illness Index; D014171:Transients and Migrants
chemical_list: D007068:Iduronidase