Hurler disease/mucopolysaccharidosis type IH (MPSIH)/-L-iduronidase deficiency

The defect in the Hurler cell is in -L-iduronidase [3-5] (Figure 77.1). The gene for -L-iduronidase has been mapped to chromosome 4p16.3 [6] and has been cloned and sequenced [7]. A number of mutations has been identified, including at least two common alleles W402X and Q70X, accounting for over half the alleles in European patients [8-10]. Heterogeneity is also evident in different mutations in other ethnic groups [11,12].