MUCOPOLYSACCHARIDOSIS TYPE II (MPS II)
Iduronate Sulfatase - IDS Sequencing
Also known as: Hunter Syndrome; I2S Deficiency; Iduronate 2-Sulfatase Deficiency
DNA ANALYSIS

Mucopolysaccharidosis type II (MPS II; also known as Hunter syndrome) is an X-linked recessive disorder with an incidence between 1:100,000 and 1:170,000 male births. It is a multisystem disorder that results from accumulation of glycosaminoglycans (heparan sulphate and dermatan sulphate). The i duronate sulfatase(IDS) gene is the only gene known to be associated with MPS II. Sequence analysis can detect 82% of the mutations in males and females with MPS II. Other mutations include exonic deletions, whole gene deletions, and IDS complex rearrangements involving the IDS2 pseudogene.

Reasons for Referral:

Confirmation of a clinical diagnosis of Mucopolysaccharidosis type II (MPSII).
Carrier testing for individuals with a positive family history for an IDS point mutation (molecular analysis of the affected relative is recommended).
Prenatal diagnosis (known mutations only).

Testing Methodology:

PCR amplification of the exons contained in the IDS gene coding region will be performed on patient genomic DNA. Direct sequencing of amplification products is performed in both the forward and reverse directions using automated fluorescence dideoxy sequencing methods.

Specimen Requirements:

Blood: EDTA (purple-top) tubes: Adults: 14 cc; Child: 6 cc; Infant: 2-3 cc
Requisition form must accompany the specimen. Prior to any genetic testing, we recommend genetic counseling and we request that the subject sign our consent statement and submit it with the sample. To receive forms, additional information or specimen collection kits, please contact the laboratory. Please call laboratory for specific requirements for prenatal testing.

Turnaround Time:

Index: 4 weeks

CPT Codes and Prices:

Index: 83891, 83898x10, 83894, 83904x20, 83909x20, 83912
Known Familial Mutation: 83891, 83898, 83894, 83904x2, 83909x2, 83912

References:

1.Bach G, Eisenberg F Jr, Cantz M, Neufeld EF (1973). The defect in the Hunter syndrome: deficiency of sulfoiduronate sulfatase. Proc. Natl. Acad. Sci. USA. 70 (7): 2134-8.
2. Nelson J, Crowhurst J, Carey B, Greed L (2003). Incidence of the mucopolysaccharidoses in Western Australia. Am. J. Med. Genet. A. 123: 310-3.
3. Baehner F, Schmiedeskamp C, Krummenauer F, Miebach E, Bajbouj M, Whybra C, Kohlschutter A, Kampmann C, Beck M (2005). Cumulative incidence rates of the mucopolysaccharidoses in Germany. J. Inherit. Metab. Dis. 28: 1011-7.

Shipping Information

Forms:

>> Gene Sequencing Requisition
>> Prenatal Requisition

Test Codes:

Index: 6390
Known Familial Mutation: 6391
Prenatal (Known Familial Mutation Only): 6392