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Science

More parents ponder cancer gene tests for kids

Women are going for breast cancer gene testing in record numbers, forcing more parents to face a tough question: should we test the kids?

American women are going for breast cancer gene testing in record numbers, forcing more parents to face a tough question: should we test the kids?

About 100,000 tests for breast cancer gene mutations were done last year in the U.S., double the number in 2005. The trend may grow even more because of widening insurance coverage and a new law banning genetic discrimination.

'The rule is, do no harm test only if you can offer something that will help' Mary-Claire King, scientist

Medical experts advise against such testing before age 25, saying that little can be done to prevent or screen for breast or ovarian cancer until then, so the knowledge would only cause needless worry.

However, new studies and interviews by the Associated Press show that many people who have BRCA gene mutations and even more of their offspring disagree. Cornell University freshman Jenna Stoller is one.

"I'm the kind of person that, like my mom, am more comfortable knowing something about myself than not knowing," said Stoller, who tested positive this year, shortly after her 18th birthday. Her mother made her wait five years after revealing her own positive test result, even though Jenna wanted to be tested at age 13.

"I remember thinking on my 17th birthday that I had another year to wait till I could make the decision for myself," she said.

Research also shows there can be benefits to at least talking about testing and inherited cancer risks with teens. It led some to quit smoking, one study found. Others, like Stoller, were advised to limit alcohol and avoid birth control pills, which can raise the risk of breast cancer though they also lower the risk of ovarian cancer.

A decade after BRCA testing began, researchers are just starting to discover the many effects that someone's positive test can have on other family members. A big issue is whether it is ethical or good to test minors.

"I've seen a fair number of parents in clinic who have really struggled with this question," said Dr. Angela Bradbury, a breast cancer specialist at Fox Chase Cancer Center in Philadelphia, who has led several studies on the topic.

Myriad Genetics Inc., based in Salt Lake City, sells the only BRCA gene test, which costs up to $3,000 US.

Men can also carry a BRCA mutation, and if either parent does, a child has a 50-50 chance of inheriting it. The mutations are most common in people of eastern European Jewish descent.

Drastic measures

Women with a faulty gene have a three to seven times greater risk of developing breast cancer and a higher risk of ovarian cancer. Men have more risk of prostate, pancreatic and other types of cancer.

Butmutations in the BRCA2 gene are found in less than 2.5 per cent of women in the United States who come down with breast cancer. Among those who carry the mutation,only about 45 per cent will actuallycome down with breast cancer by the time they reach 70.

To lower risk, women can consider anti-estrogen drugs or having their breasts or ovaries removed. But these drastic measures are not advised for very young women. Even mammograms are not advised till age 25, because cancer is rare before then.

So the American Society of Clinical Oncology and other groups say that when the risk of childhood cancer is low and nothing can be done to lower it, children should not be given gene tests.

"The rule is, do no harm test only if you can offer something that will help," said Mary-Claire King, the University of Washington scientist who in 1990 discovered the first breast cancer predisposition gene, BRCA1.

"The life of a young girl is complicated enough already. There is nothing about it that needs to change" if she carries one of these genes, King said.

In Canada, no regulations govern the claims and practices of the genetic testing industry. Governments also receive little guidance on whethera specific gene test is worth funding.

Wanting to know

But some parents are testing girls before they even have breasts, let alone cancer risk. One woman had her four-year-old daughter tested, said Sue Friedman, executive director of FORCE: Facing Our Risk of Cancer Empowered, a Tampa-based support group for people with BRCA genes.

Another woman tested two very young children several years ago at Baptist Health South Florida in Miami.

"We wanted to know it's as simple as that," she said. "Kids are born with all kinds of defects that parents have to make decisions about. I just think this is one of those things," said the woman, who spoke on condition of anonymity because of privacy concerns for her children.

Rae Wruble, a nurse and genetics adviser at Baptist Health, said this woman was the only one in more than 900 she has counselled who chose to test very young children. Wruble said she always tells patients that cancer groups recommend against testing minors and why. But she admitted: "If I had young children, I would have tested them because that's just the kind of person I am I would want to know."

Most parents do not peek inside their child's gene toolbox, Friedman said. "It does deny the actual patient informed consent."

"I feel very strongly that people should not test their children, but children should make their own decision," said Jill Stoller, a New Jersey pediatrician who is the mother of Jenna, the Cornell student.

Counselling tempers response

Jenna had hours of counselling before doctors agreed that for her, testing was the right choice. However, Jennifer Scalia Wilbur, a counsellor at Women and Infants Hospital in Providence, R.I., told of a 19-year-old who had testing without counselling and now wants to remove her breasts and not have children.

"It was extremely distressing" to talk with her now and try to correct her overly dire outlook, she said.

Wanting to test minors can be a knee-jerk response that changes after counselling. Tammy LeVasseur of North Attleboro, Mass., at first thought she wanted all three of her daughters to be tested after she learned of her own positive result in July.

She later decided to encourage testing for her two oldest daughters, ages 26 and 28, who had already finished having children, but not for Jessica, who just turned 17.

"I want to wait until I'm in my 20s," Jessica LeVasseur said. "They wouldn't do anything about it. There's no reason to worry now. I'd rather just be able to finish my teenage years without worrying about that."