In choosing a sperm donor,a roll of genetic dice

Donated eggs pose a risk too,but the threat of genetic harm from sperm donation is much greater. Sperm donors are no more likely to carry genetic diseases than anybody else,but they can father a far greater number of children: 50,100 or even 150,each a potential inheritor of flawed genes,and each a vector for making those genes more pervasive in the general population.

The scale of the problem is only now becoming apparent. “There needs to be oversight,and some regulation of the industry,” Kramer said. It is not known how many children are born each year using sperm donors. By some estimates,there are more than a million children in the United States conceived with donated sperm or eggs.

Health administrative centres like the US Food and Drug Administration require sperm donors be tested for communicable diseases,but there is usually no requirement that sperm banks screen for genetic diseases. Some of the betters ones do anyway,which encourages sperm banks to test donors for conditions like cystic fibrosis and mental retardation when there is a family history of the disease. Generally,the donor himself is tested,not his sperm.

But compliance is usually not obligatory,and genetic testing practices vary widely. Critics of the industry are calling for mandatory and consistent medical and genetic testing of all donors.

“In this day and age,when you have genetic testing available for about $200,there’s no reason sperm banks can’t provide this for clients,” said Kramer.

The fertility industry,however,has long resisted the idea.

“Human reproduction is an inherently risky proposition and it always will be,so it’s impossible to remove all the risk and uncertainty of reproducing,” said Sean Tipton,director of public affairs for the American Society for Reproductive Medicine. “You’ll never be able to catch everything. As the technical capabilities to do genetic testing and screenings improve,the banks will do that. But it will be incredibly expensive to test for everything.”

A lack of regulatory record-keeping also makes it difficult for sperm banks to warn related families,or even donors,when a genetic illness is discovered in one or more children. And donor families are not required to report births or illnesses to the sperm banks. Since the clinic has no way to know a donor’s sperm is flawed,it may continue to be sold long after problems have surfaced.