Can Men Make Eggs?

The debate about the use of embryonic stem cells to grow replacement tissue (brain, liver, etc.) is about to get much more complex now that scientists have turned stem cells from mouse embryos into viable eggs. The report in Science set researchers' imaginations ablaze. Could this technique provide an endless supply of human eggs? And since scientists turned cells from both female and male mice into eggs, could it overturn traditional notions of parenthood? Could males make egg cells? Could gay couples produce genetic offspring? So far, the research holds promise only for gay mice.

GOING WITH THE GRAIN Does a high-fiber diet protect against colon cancer or not? Scientists have been going back and forth on the question for some time. The two most recent studies, published in the British journal Lancet, may not have the last word on the subject, but at least they are in agreement: both suggest that a high-fiber diet lowers the risk substantially. Study subjects who ate about 35 g of dietary fiber a day (from whole grains, cereals and fruits) had a lower risk--27% to 40% lower — of developing colon cancer than those eating 15 g or less.