Mucopolysaccharidosis I (Hurlers Syndrome)


MPS I (Hurler Syndrome) is an autosomal recessive mucopolysaccharide storage disorder caused by a deficiency of the lysosomal enzyme a-iduronidase. This deficiency results in the accumulation of heparan and dermatan sulphates in the lysosome. MPS I is a multisystemic disorder characterised by facial dysmorphism, dysostosis multiplex, and neurological deterioration. There is a broad spectrum of disease severity, in the severe form, death usually occurs during the first or second decade. Milder forms of the disorder show less rapid progression of somatic symptoms and no neurological deterioration. The disorder is divided into 3 disease sub-types according to disease symptoms. MPS I is caused by mutations in the IDUA gene, which codes for the enzyme a-iduronidase. The gene is situated on chromosome 4 at position p16.3. A number of common or recurrent mutations exist in the Caucasian population, but in other populations, many are unique to the family and include a variety of point mutations, deletions, insertions and splice junction defects.

Referral information

This service is funded by the National Commissioning Group (NCG). Samples received from England, Northern Ireland and Scotland are charged to NCG with the majority of samples being received from The Willink Metabolic Unit. New patients are initially diagnosed by enzyme analysis; therefore patients will usually have already been referred to a relevant NCG centre before DNA analysis is requested. Funding from the NCG also covers carrier detection, by DNA analysis, for family members.

Price & reporting times

This service is funded by the National Commissioning Group and is free to NHS referrers from England, Northern Ireland and Scotland. In other cases please contact the lab for prices.

Test Price NHS (£) Price non- NHS (£ ) TRT (calendar days)
Mutation scanning POA POA 56
Single mutation test POA POA 28
Urgent/Predictive single mutation test POA POA 14

Test validation & quality assurance - information for users

IDUA mutations can be identified in >95% of affected individuals. The laboratory is UKAS assessed against ISO 15189 standards.

Sample requirements

4ml EDTA blood sample. If Willink laboratory testing is required, a 10ml urine sample is required

Referral guidelines

Please see our referral guidelines for more information.

OMIM Number(s) - 607015

Gene(s) - IDUA