Researchers solve 'frustrating' horned cattle mystery

Genetics breakthrough could make horned cattle a rarity in Northern Australia Thu 11 Jun 2026 at 9:33am In short: A new test has helped solve the mystery of why some cattle that were clearly born without horns were still returning "horned" results in commercial DNA tests. Researchers at the University of Queensland have identified a previously undetected gene variant in tropical cattle breeds, such as brahmans, solving a mystery that has frustrated producers for years. What's next? Researchers will look at how these hornless genetics first entered Australian cattle populations. Horned cattle could become a rarity in northern Australia, following a major genetics breakthrough that will allow producers to breed more accurately for naturally hornless animals. Researchers at the University of Queensland have identified a previously undetected gene variant in tropical cattle breeds, such as brahmans, solving a mystery that has frustrated producers for years. Until now, some cattle that were clearly born without horns were still returning "horned" results in commercial DNA tests. Queensland Alliance for Agriculture and Food Innovation associate professor Elizabeth Ross said the issue was not that the tests were wrong, but that they were simply not looking for all possible hornless gene variants. "There are four different genetic variants that cause hornlessness in cattle, and the commercial tests were only tracking two of them," Dr Ross said. "We discovered the other two were circulating in Australian tropical cattle populations, but no-one had identified them before." Discovery of the polledG variant The newly discovered variant Guarani, or polledG, originally found in Brazil, has now been incorporated into a commercial test available to Australian producers. Polled cattle, animals naturally born without horns, are becoming increasingly desirable among cattle producers across the northern beef industry because they improve workplace safety, reduce labour costs and eliminate the need for dehorning. Dr Ross said the genetic breakthrough would help producers make more informed breeding decisions and increase the number of naturally hornless cattle in their herds. "It means producers can now have confidence that the genetic results match the animal standing in front of them,"she said. The discovery followed concerns raised by members of the Australian Brahman Breeders Association, after repeated inconsistencies between genetic testing and what producers were physically seeing in their cattle. "They had one of their members who kept having this issue where they would send their DNA off for testing, and they knew that their animal had no horns," Dr Ross said. "It was a polled animal but the genetic test kept coming back saying that it had horns. The producer was obviously a bit frustrated because they were looking at the animal and this animal had no horns." Researchers used advanced long-read DNA sequencing technology to analyse the cattle genome in far greater detail than standard commercial testing methods. "Over 100,000 base pairs of the animal's genome are duplicated and, when that duplication happens, the animals just don't grow horns," Dr Ross explained. "So, the test picks up that duplication and then producers are able to get an outcome, which tells them whether or not their animal carries a copy of this hornless trait." An industry excited Whitsundays cattle producer Lawson Camm purchased his first polled bull in 2012. He said demand for polled brahmans had surged over the past decade. "One of the biggest changes that we've had in recent years has been moving to poll genetics, and that's been industry-driven by clients; it's also been a management issue," he said. "I sold a big percentage of our bulls into northern Queensland and into the Northern Territory, and a lot of those producers want poll genetics nowadays." Breeder Ray Vella, from near Proserpine, said naturally hornless cattle were especially important in the tropics, where wet season conditions could make dehorning difficult. "It's very labour-intensive, and you can lose calves from bleeding out,"he said. "The poll gene is probably first on the list now for a lot of producers." While the discovery answers one longstanding question for the cattle industry, researchers say it has also raised another — how these hornless genetics first entered Australian cattle populations. The test was made available to Australian producers from May 2026.