성적교배 없이 정액생산이

교배를 통하여서만 정액이 될 수컷의 세포가 교배없이 정액으로 만들어졌다.

이 기술을 통하여 어느 날 바라는 종류의 동물을 조속히 만들어 낼 수 있고

속성으로 육성할 수도 있으며 멸종위기의 동물도 번식 시킬 수 있고좋아하는

회 초밥물고기를 더 많이 만들어 낼 수 있다고 2월7일에 발간 된 국립 과학

아카데미에서 발표 되어졌다. 고기가 갖고 있는 양성에 주목하여 또 스스로 교배할

수 있는 것을 오래 전부터 알고 있었기에 가능했다한다. 수컷 한마리만 있으면

멸종 위기의 동물을 재생산 해낼 수 있다고. 서울대 수의대 얘기가 아니고

일본 동경대학의 연구 발표다.

Sperm Cells Turned into Eggs

Ker Than
LiveScience Staff Writer
LiveScience.com Tue Feb 7, 6:00 AM ET

Scientists have tricked male fish cells that were destined to become sperm into switching sex and

becoming eggs instead. The technique could one day be used to quickly produce animals with desired traits,

speed up breeding programs and help repopulate dwindling populations of endangered species or creating

sushi on demand, the researchers said. The finding is detailed in the Feb. 7 issue of the journal for the Proceedings

of the National Academy of Sciences.

Sexually indifferent cells

Scientists have long known that some fish are able to switch their sex, either spontaneously or when exposed

to steroids. This led them to suspect that a subset of the population of cells in male fish that normally become sperm,

called spermatogonia, might be stem cells that have the potential to become either sperm or eggs.

To test their hypothesis, the researchers isolated spermatogonia from the testes of adult rainbow trout and transplanted

them into newly hatched trout of both sexes. In male hatchlings, the transplanted cells developed into sperm, while in

females they developed into eggs. The scientists are currently looking into whether eggs could be transformed into

sperm. Other researchers have successfully produced sperm from mice stem cells. Sushi on demand

The technique could be used to rapidly breed inbred strains of domestic or research animals with desired genetic traits,

the researchers write. Tokyo University's Goro Yoshizaki, the study's principal investigator, told LiveScience the

technique could be used to establish surrogate breeding programs for animals such as the blue fin tuna, a fish popular

for sushi and sashimi in Japan and elsewhere. Populations of the fish are declining worldwide and adult blue fin tunas are expensive and difficult to keep in captivity. One solution, Yoshizaki said, is to isolate the spermatogonia from adult male

tunas and transplant them into both male and female hatchlings of a smaller fish species, such as mackerel.

Once transplanted, the germ cells would differentiate into sperm and eggs. The mackerel would then be allowed to

reproduce normally, but they would produce tuna instead of mackerel.

The technique could also be used to help save endangered fish species, Goro added. A single male endangered fish

could be used to repopulate an entire species. "Even if the species is extinct, we can restore them by transplanting

them into closely related species," Goro said.

• Stem Cells in Lab Make Sperm
• Well Endowed Fish Get the Girls
• Five Deep-Sea Fish on Brink of Extinction
• Oops! Scientists Nudge Fish Closer to Extinction
• Pollution Blamed for Intersex Fish

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