SSS 2009-12-10
时间:2018-12-24 作者:英语课 分类:Scientific American(十二)月
Little girls are made of sugar and spice and, according to a study published in the journal Cell, a fierce determination to maintain their girlishness. Because it seems that a single gene 1 keeps their ovaries from turning into testes.
Scientists have long thought that the ovary is the default setting for developing sex organs. That’s because the male Y chromosome 2 comes equipped with a so-called sex determination gene called SRY. If SRY is missing, the gonad develops into an ovary, even if the embryo 3 is male. Add SRY to a female embryo, it’ll make testes. But the new work implies that sex determination is not that simple.
Okay, buckle 4 up. See, the SRY gene makes a male by turning on another gene called Sox9. But it turns out that females have a trump 5 card called FOX L2. FOX L2 switches off Sox9, which lets ovaries be ovaries. The surprise is that girls have to keep the FOX L2 gene active forever. In studies of mice, if FOX L2 gets shut off, even in an adult, the ovaries will turn into testes. Which for a girl means ball game over.
—Karen Hopkin
- A single gene may have many effects.单一基因可能具有很多种效应。
- The targeting of gene therapy has been paid close attention.其中基因治疗的靶向性是值得密切关注的问题之一。
- Chromosome material with exhibits of such behaviour is called heterochromatin.表现这种现象的染色体物质叫做异染色质。
- A segment of the chromosome may become lost,resulting in a deletion.染色体的一个片段可能会丢失,结果产生染色体的缺失。
- They are engaging in an embryo research.他们正在进行一项胚胎研究。
- The project was barely in embryo.该计划只是个雏形。