LABOKLIN (UK)| Genetic Diseases | Cats| Glycogen Storage Disease ( GSD ) Type IV

Glycogen Storage Disease ( GSD ) Type IV

Test number: 8113
Gene: GSDIV
Price: £ 48.00 (including VAT)

Update 25/11/2011 price of Glycogen Storage Disease ( GSD ) Type IV in Norwegian Forest Cats has been reduced to £49.95 (VAT included)

Breed

Norwegian Forest Cat .

The Disease

Glycogen storage disease type IV (GSD IV) of the Norwegian forest cat is an inherited abnormality of glucose metabolism. Normally, excess glucose is stored in many tissues as glycogen. If energy is needed, glucose molecules are removed from glycogen. The ability to add and remove glucose molecules from glycogen efficiently is dependent on its highly branched structure. The glycogen branching enzyme (GBE) is an enzyme of glycogen synthesis necessary to produce the branching structure. Deficiency of GBE activity leads to abnormal glycogen accumulation in myocytes, hepatocytes, and neurones, causing variably progressive, benign to lethal organ dysfunctions. Most affected kittens die at or soon after bird, presumably due to hypoglycemia. Survivors of the perinatal period appear clinically normal until onset of progressive neuromuscular degeneration at 5 month of age.

Trait of Inheritance

The mutation and inheritance The mutation in the GBE1 gene which has been suggested to cause GSD-IV has recently been published by the group of John C. Fyfe at the University of Michigan, USA. GSD IV is inherited as an autosomal recessive trait. So there are three conditions a cat can be: it can be clear or homozygous normal (genotype N/N) meaning that it does not carry the mutation and will not develop GSD IV. Since it also cannot pass the mutation onto its offspring, it can be mated to any other cat. A cat which has one copy of the GBE1 gene with the mutation and one copy without the mutation is called a carrier or heterozygous (genotype N/GSD-IV); while it will not be affected by GSD IV, it can pass the mutation onto its offspring and should therefore only be mated to clear cats. Affected kitten have two GBE1 gene copies with the mutation (genotype GSDIV/ GSD-IV or homozygous affected); they will always pass the mutated gene onto their offspring.

Inheritance : AUTOSOMAL RECESSIVE trait

Sire	Dam	Offspring

clear	clear	100% clear

clear	carrier	50% clear + 50% carriers

clear	affected	100% carriers

carrier	clear	50% clear + 50% carriers

carrier	carrier	25% clear + 25% affected + 50% carriers

carrier	affected	50% carriers + 50% affected

affected	clear	100% carriers

affected	carrier	50% carriers + 50% affected

affected	affected	100% affected

Clear

Genotype: N / N [ Homozygous normal ]

The cat is noncarrier of the mutant gene.
It is very unlikely that the cat will develop Glycogen Storage Disease ( GSD ) Type IV. The cat will never pass the mutation to its offspring, and therefore it can be bred to any other cat.

Carrier

Genotype: N / GSDIV [ Heterozygous ]

The cat carries one copy of the mutant gene and one copy of the normal gene.
It is very unlikely that the cat will develop Glycogen Storage Disease ( GSD ) Type IV but since it carries the mutant gene, it can pass it on to its offspring with the probability of 50%.
Carriers should only be bred to clear cats.
Avoid breeding carrier to carrier because 25% of their offspring is expected to be affected (see table above)

Affected

Genotype: GSDIV / GSDIV [ Homozygous mutant ]

The cat carries two copies of the mutant gene and therefore it will pass the mutant gene to its entire offspring.
The cat is likely to develop Glycogen Storage Disease ( GSD ) Type IV and will pass the mutant gene to its entire offspring

Description

By DNA testing, the responsible mutation can be shown directly. This method provides a very high accuracy test and can be done at any age. It offers the possibility to distinguish not only between affected and clear cats, but also to identify clinically healthy carriers. This is an essential information for controlling the disease in the breed, as carriers are able to spread the disease in the population, but can not be identified by means of common laboratory diagnostic. To ensure maximum test reliability, the test is always performed in two independent test runs per sample.

Sample Requirements

Whole blood in EDTA tube (0.5 - 1 ml) or Buccal Swabs.

Turnaround

2 - 3 weeks

We will run this test 2 independant times on your sample to ensure that the result is 100% accurate

Price

£ 48.00 (including VAT)