How Much Can We Decide About Baby's Genes?

A British couple has used in vitro fertilization to keep their child free of a gene that promotes breast cancer -- an advancement supported by ethicists who worry, at the same time, where it will lead.

The Assisted Conception Unit at University College London Hospital announced this weekend that it had produced the first baby in the United Kingdom guaranteed not to have the breast cancer gene, which is thought to raise the risk of the disease to between 40 and 85 percent.

The father of the unborn child had a family history of breast cancer, with his sister, mother, grandmother and cousin all suffering from it at some point. Doctors scanned 11 fertilized embryos and implanted two of them that were found to be free of the breast cancer gene in the mother, who is now 14 weeks pregnant.

Doctors are quick to caution that this does not come close to eliminating the breast cancer risk entirely.

"Even if the baby doesn't have the breast cancer gene abnormality, that doesn't mean she won't get breast cancer," said Dr. Marisa Weiss, president and founder of, and author of the upcoming breast cancer book "Taking Care of Your 'Girls'."

The screening represents a new phase in genetic testing on embryos, because it looks at a gene that poses a risk, rather than a disease itself, said Dr. Sherman Silber, director of the Infertility Center of St. Louis at St. Luke's Hospital.

He said that the idea of prescreening fertilized embryos has been around since 1990, when it was first used to avoid having children with cystic fibrosis.

A similar phenomenon has taken place, Silber noted, in families that have had autistic children and would like to avoid having another.

"For autism already in couples that have children, they're requesting [pre-implantation diagnosis] with sex selection, because, obviously, it's so much more common in boys than in girls," Silber said. "There are couples that have had several children with autism ... that have been requesting sex selection just to have only females."

Dodging Disease ... Before Birth

But, in this case, how much will gene screening help the baby when it reaches the age when breast cancer risks become a reality?

Weiss noted that in the vast majority of cases, breast cancer is related to a change in the genes later in life, and not something inherited.

"Nine out of 10 times, the breast cancer is due to an acquired genetic abnormality," Weiss said.

While ethical experts call this issue a slippery slope, Weiss sees it as a highly beneficial treatment in this circumstance.

"In that family, that gene was a curse," she said. "For whatever reason, every woman seemed to have it."

While the breast cancer gene typically sorts itself out 50-50, Weiss noted that not only did most women in the father's family seem to have the gene, but those who had it inevitably seemed to develop a highly aggressive form of breast cancer.

"It's good to have this option available for families who are profoundly affected by this disease, who want this option," said Weiss. "This story speaks to the importance of genetic counseling, where this decision can be made with best advice, the best information, guidance, respect, and sensitivity -- free of self-righteous judgment."

While the child would still eventually have a risk without the gene, "12 percent is a hell of a lot lower than 40 to 85 percent, the risk that would go along with a genetic abnormality," Weiss said.

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