There is an epidemic of renal disease in the Australian Aboriginal population. While renal disease is associated with diabetes and hypertension, amongst the people of the Tiwi Islands there is a far greater incidence of renal disease than would be expected given the incidence of other diseases. The Tiwi are a genetic isolate and therefore are likely to be an ideal population to study the genetic basis of the indigenous renal disease. I will be presenting the results of a genome wide association study in the Tiwi using a 500K Affymetrix Array. Association was carried out, while adjusting for known and unknown relationships.
We have identified preliminary evidence of association of renal disease to an array of genes encoding xenobiotic detoxifying enzymes. Our hypothesis is that the Tiwi nephropathy is caused by a nephrotoxin associated with, or intensified by, the change to a Westernised lifestyle, be it diet or living conditions or both, which is unable to be detoxified by the Tiwi. We are in the process of testing this hypothesis by comparing Tiwi urine samples to controls, using chromatography.