|
|
|
SMA (Spinal Muscular Atrophy )
Test number: 8123
Gene: SMA
Price: £ 48.00 (including VAT)
|
|
|
|
|
| |
|
The Disease |
SMA is a disorder caused by death of spinal cord neurons that activate skeletal muscles of the trunk and limbs. Loss of neurons in the first few months of life leads to muscle weakness and atrophy that first becomes apparent at 3-4 months of age.
Affected kittens develop an odd gait with a sway of the hindquarters and stand with the hocks nearly touching. They may also stand with toes out in the front.
By 5-6 months of age they are too weak in the hindquarters to readily jump up on furniture and often have a clumsy landing when jumping down. The long hair Maine Coon cats may hide it, but careful feeling of the limbs will reveal reduced muscle mass. |
|
|
|
|
Trait of Inheritance |
SMA 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 SMA. 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 gene with the mutation and one copy without the mutation is called a carrier or heterozygous (genotype N/SMA); while it will not be affected by SMA, it can pass the mutation onto its offspring and should therefore only be mated to clear cats.
Affected kitten have two gene copies with the mutation (genotype SMA/SMA 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 SMA (Spinal Muscular Atrophy ). The cat will never pass the mutation to its offspring, and therefore it can be bred to any other cat.
Carrier
Genotype: N / SMA [ 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 SMA (Spinal Muscular Atrophy ) 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: SMA / SMA [ 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 SMA (Spinal Muscular Atrophy ) 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 test with a very high accuracy 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. . |
|
|
| |
|
Price
|
|
£ 48.00 (including VAT)
|
|
|
 |
|
|
|
|
| See also: |
|
|
|
