Definition

Mucopolysaccharidosis type II (Hunter syndrome) presents with accumulation of glycosaminoglycans due to variants in the region of the X-linked IDS gene that encodes the iduronate-2-sulfatase enzyme. The severe form (~75%) presents with progressive skeletal deformities, airway obstruction, cardiomyopathy, and neurological decline; the typical absence of corneal clouding is a distinguishing feature from Hurler syndrome.

Gene/region examined

IDS - Exon 1, IDS - Exon 2, IDS - Exon 3, IDS - Exon 4, IDS - Exon 5, IDS - Exon 6, IDS - Exon 7, IDS - Exon 8, IDS - Exon 9

Method

Sequence analysis

Accepted sample types

EDTA blood, AF, CVS

Inheritance

Hereditary, X-linked recessive.

Related Tests

Inheritance Patterns

Describes how a genetic condition is passed on within a family. There are five main patterns

Go to term →

Carrier (Heterozygous / Homozygous)

Why it matters: In autosomal recessive inheritance, when each parent is a carrier (while both appear healthy), the chance of their child being born with the disease is 25% in each

Go to term →

VUS (Variant of Uncertain Significance)

This is the situation where the test has detected a change in the DNA, but the role of this change in the development of disease is unconfirmed.

Go to term →

How to Read a Genetic Test Result (Positive / Negative / VUS)

A genetic test result falls into three main categories

Go to term →

Types of Genetic Tests

A genetic test is a type of medical test that detects changes in genes, chromosomes or proteins. Today there are more than 77,000 genetic tests available.

Go to term →