The discovery, reported in the March issue of Nature Genetics, may improve prospects for gene testing and diagnosis of the life-threatening disease.
Autosomal recessive polycystic kidney disease (PKD), sometimes called ‘infantile PKD', causes several fluid-filled cysts to form in the kidneys and abnormalities in the liver, often resulting in neonatal death.
Two genes have been identified for the more common, dominant form of PKD.
However, the genetic cause of the recessive type, inherited only when both parents carry an abnormal copy of the disease gene, has proved harder to find.
| The gene responsible for autosomal recessive PKD is found on chromosome 6.
Over seven years ago, German scientists narrowed down the "neighborhood" of the disease gene to a region on chromosome 6.
Now, Peter Harris and colleagues at the Mayo Clinic in Minnesota have honed in on the human gene by first finding a mutation in the gene that causes a strikingly similar disease in rats.
By exploiting the similarities between rat and human genes, the researchers isolated a gene on chromosome 6 that is mutated in patients with autosomal recessive PKD.
The gene is predicted to encode a very large protein, dubbed fibrocystin.