Dwarfism Mutation Identified in Dogs

A recent study discusses a dwarf mutation found in dogs known as the ITGA10 gene, which causes chondroydysplasia in two dog breeds, known as the Norwegian Elkhound and the Karelian Bear Dog.

The study revealed that the new gene in dogs shows information for a similar problem in humans.

The study notes the following, via a press release: "The ITGA10 mutation causes autosomal recessive disproportionate short-stature dwarfism of varying severity. The appearance of affected dogs is characterized considerably shorter limbs than normal dogs, and other skeletal abnormalities may follow, including bowed forearms, abnormal digits, and malformed femoral heads.

"The ITGA10 gene codes for an integrin subunit that assembles into a cartilage-specific collagen receptor, found in the growth plates of long bones. The receptor is important for the process of endochondral ossification, in which the cartilage cells first proliferate, and are then replaced by bone tissue. Accordingly, several abnormalities have been found in the growth plates of affected dogs both in radiographic and histological examinations."

Researchers looked at specific causes of the mutation on the canine chromosome 17 by comparing the genomes of affected and healthy dogs. Further analysis of this chromosomal region revealed a single nucleotide change in the ITGA10 gene, which disrupts the gene by introducing signal that prematurely ends the production of the encoded integrin subunit.

"Because of the premature stop codon, the full length integrin subunit is never made, and consequently, there are no functional receptors in the affected dogs' growth plates. This causes the growth disturbances", explains Professor Lohi, via the release. He continues on that "Several collagen mutations have been previously found in different growth disorders but this is only the second collagen receptor that has been linked to inherited chondrodysplasia. Our canine disease model offers new possibilities to study growth plate biology".

The results of the study show possible implications for human medicine. "Humans also suffer from different types of inherited chondrodysplasia, and the ITGA10 gene could represent a good candidate gene for some of these disorders, which still have an unknown genetic cause", tells Kaisa Kyöstilä, the first author of the paper. "We have already begun screening human patients for mutations in the gene."

More information regarding the study can be found in the journal Plus ONE.