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Israeli scientists discover genetic method for biasing mammalian sex ratios

The research, by a team of researchers from Tel Aviv University, could allow livestock producers to choose the sex of animals’ offspring.

Israeli cowboys collect a herd of cattle to separate the bulls from the females, at their farms in Northern Israel. June 12, 2018. Photo by Maor Kinsbursky/Flash90.
Israeli cowboys collect a herd of cattle to separate the bulls from the females, at their farms in Northern Israel. June 12, 2018. Photo by Maor Kinsbursky/Flash90.

Israeli scientists from Tel Aviv University have discovered a genetic mechanism for biasing the sex ratio of mammalian populations so that only offspring of a desired gender are produced. The finding, which was published in the peer-reviewed “EMBO Reports” journal on Monday, could have major implications, especially for the agricultural industry.

The researchers—Professor Udi Qimron, Dr. Ido Yosef and Dr. Motti Gerlic of the Department of Clinical Microbiology and Immunology at Tel Aviv University’s Sackler School of Medicine—were able to manipulate the sex ratio of genetically engineered mice to a 95:5 female-to-male ratio. The usual ratio is 1:1.

According to the scientists, while biasing of the sex ratios of plants, insects, crustaceans and fish has been demonstrated in the past using both genetic and non‐genetic approaches, this study marks the first time that the sex ratio of a mammalian population has been demonstrated using a genetic method.

“The research provides the world’s first proof-of-concept for mammals to genetically produce only female progeny,” said Qimron in a statement put out by the university. “We proved the concept in mouse models, but the concept could also be demonstrated in cattle, swine, goats, chickens and other animals.”

According to Qimron, the system can also be used to produce only males.

“We believe that the producers of cattle, swine and chicken may benefit greatly from the technology,” he said.

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