October 11, 2001

Contact: Dr. Mervyn Jacobson
XY Inc., USA
(970) 310-3857

ANOTHER XY Inc., WORLD FIRST: THIS TIME WITH SHEEP

     SYDNEY, AUSTRALIA--United States biotechnology firm XY Inc. has achieved another scientific breakthrough in Australia and abroad: The first sex-selected lambs in Australia--and the world--have been produced using advanced sperm-sorting techniques needed for commercialization.
      The healthy Australian lambs are the first ever to be conceived using low doses of sperm that were sorted, then frozen, thawed and artificially inseminated into ewes.
     " The birth of the lambs in Australia proves the sperm-sorting technique, combined with freezing, thawing and artificial insemination, is now sufficiently robust in sheep to work outside the research lab," said Mervyn Jacobson, chief executive officer and president of XY Inc.
      Jacobson believes XY Inc., will commercialize sex-selection combined with artificial insemination within the next two-three years in the Australian sheep industry.
      Researchers from the University of Sydney and XY Inc. achieved expected success rates in producing the desired gender of 25 lambs; a 94-percent success rate for pre-selected females and a 100-percent success rate for pre-selected males. The resulting overall pre-selection accuracy rate stands at 96-percent.
      Sheep breeders, like all other livestock producers, typically produce a 50:50 ratio of male and female offspring. Livestock breeders have strong interest in any sex-selection technology that might offer 90-percent accuracy rates or better.
      XY Inc. is the only company in the world licensed to pursue sperm sorting in non-human mammals using U.S. Department of Agriculture methods.
      Sperm sorting involves separating sperm that carry female-producing X chromosomes from sperm that carry male-producing Y chromosomes. The procedure sorts the sperm; it does not genetically alter the sperm-and therefore does not harm the animal--in any way.
      The University of Sydney's Centre for Advanced Technologies in Animal Genetics and Reproduction-or ReproGen--is the first organization in Australia to establish, in partnership with XY Inc., a sperm-sorting facility for livestock. Associate Professor Chis Maxwell and his team are internationally recognized animal-reproductive biologists and the world's leading sperm-sorting team for sheep, said Jacobson.
      Benefits to sheep breeders. Low-dose, sorted sperm that has been frozen and thawed has benefits to sheep breeders. Because the sex of the animal can be determined prior to conception, sheep breeders can select more female lambs for breeding or more male lambs to produce superior rams.
     " For example, stud breeders who want high-quality rams for superior wool production want only to produce rams from the best females," Maxwell said. "Sperm sorting really affords breeders more flexibility."
      In addition, sperm that is frozen and then thawed means breeders can use sperm stored for a period of time or transported over long distances.
      The research team achieved another world first: It usually takes 60-million sperm to impregnate a ewe using standard artificial-insemination techniques. The XY/University of Sydney team accomplished the pregnancies using only four-million sperm.
      The sperm-sorting technology could have a positive impact on Australia's wool, lamb and mutton industries, said Maxwell. Australia boasts more than 120-million sheep and lambs nationwide. The sheep industry is slightly behind cattle production in terms of national-export earnings.
      Already, thousands of successful and healthy pregnancies have occurred among cattle, horses, pigs and sheep worldwide using XY Inc.'s sperm-sorting method - which features a high-speed cell-sorting machine called a MoFlo -- combined with artificial insemination.      The separation procedure is based on a 4.2-percent difference in DNA content between "female" and "male"-producing sperm. High concentrations of sperm with the selected chromosome are then used to fertilize female animals.
      In the trial, begun on Feb. 26, that produced the 25 lambs, researchers inseminated select ewes with either X-bearing "female" sperm, Y-bearing "male" sperm or unsorted sperm (control group). From July 24-29, 12 ewes in the X-treatment group produced 17 female lambs and one male lamb-a 94.4- percent success rate. Seven ewes in the Y-treatment group produced eight male lambs-a 100-percent success rate. The 26 ewes in the control group produced 20 male and 19 female lambs-the expected 51-percent to 49-percent ratio.
      For more information on XY Inc., call 970-493-3113 or visit www.xyinc.com. For more information on the University of Sydney's ReproGen research team, call Chis Maxwell at 011 61 2 9351 4864 or visit www.usyd.edu.au/su/vetfac/.