As California’s Institute for Regenerative Medicine, created after a state referendum last year, gears up for therapeutic cloning, questions are being asked about where it will obtain the huge number of eggs it will need for its experiments. “Payment to these women for their eggs, even if it is considered reimbursement, would create an economic inducement for women to put themselves at risk,” says Marcy Darnovsky, associate director of the Center for Genetics and Society in Oakland. “This would be especially true for poor and young women.” Francine Coeytaux, of the Pro-Choice Alliance for Responsible Research, complains that “this new technology will require eggs from thousands of women”.

The experience of the sole US institution to harvest eggs for research, Bedford Stem Cell Research Foundation, near Boston, is not promising. It had to suspend its research four times since 2001 after exhausting its funds. It paid about 20 women US$4,000 each plus expenses, but its expenses were about $25,000.

Meanwhile, a few California lawmakers are trying to gain some control over the Institute, which has been authorised to spend $300 million a year in research grants for the next 10 years. However, the referendum explicitly prohibits the legislature from amending the initiative for three years. State Senator Deborah Ortiz, a critic of the Institute, says another referendum to amend last year’s referendum may be in order.