Australia's iconic dingo may be the world's oldest breed of dog, according a major new DNA study that is likely to boost conservation efforts. The international study has found the dingo and its close relation, the rare New Guinea singing dog, bear the closest genetic similarity to wolves of all breeds tested. The research, published in science journal Nature, appears to confirm widely held theories about the dingo's history. It involved testing nearly 1,000 dogs of 85 different breeds as well as hundreds of wolves. 'This gives us a huge weight of evidence supporting the theory that the dingo is quite distinct from all modern dog breeds,' said joint author Alan Wilton, of Sydney's University of New South Wales. 'It's a bit of information that could be important to the conservation issue. If it's distinct from domestic dogs there may be scientific reasons for conserving the dingo.' Dingoes and the singing dog, named for its distinctive multi-pitched howl, have developed in isolation from other breeds for thousands of years. Dingoes were introduced to Australia from Indonesia about 5,000 years ago. Dingoes have come under threat from rampant inter-breeding, prompting calls to maintain their genetic purity. Wilton said 80 percent of dingoes on Australia's east coast were thought to be mixed-breed. 