The temptation to test

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The temptation to test

More often than not, the advantages of genetic testing aren't so

clear-cut. And even " normal " results aren't a guarantee of good

health.

Children could be screened for genetic diseases, but parents should

let them decide later. Why? Early detection doesn't mean a cure, and

there could be psychological risks.

http://www.latimes.com/features/printedition/health/la-he-

themd3mar03,1,7534696.story?ctrack=4 & cset=true

By Ulene, Special to The Times

When it comes to medical care, my husband and I generally call the

shots in our family.

Most people would agree that this is an appropriate role for us to

play, but certain medical decisions aren't normally the purview of

parents. Nor should they be. Foremost among them is the decision to

screen children for some genetic diseases.

During the last 25 years, the number of genetic tests has increased

rapidly. It's now possible to identify alterations, or mutations,

that increase the risk of a variety of diseases -- sickle cell

anemia, cystic fibrosis, heart disease, diabetes and cancer to name a

few.

Sometimes identifying a mutation early in life is beneficial. Newborn

screenings for hypothyroidism and the metabolic disorder

phenylketonuria, for example, can prevent potentially irreversible

consequences that may develop if the conditions are left undiagnosed

and untreated.

When genetic testing offers such obvious benefits to a child, the

medical community generally agrees that parents should consent to it -

- even seek it out. However, more often than not, the advantages of

testing are not so clear-cut.

The ability to detect a genetic abnormality often precedes the

development of the disease by many years. And, for many conditions,

knowing that a child is genetically predisposed offers only anguish,

not solutions -- no treatments can prevent the diseases or delay

their onset.

Perhaps the most notable example of this is Huntington's disease, an

untreatable and debilitating neurological condition that causes

uncontrollable body movements and damages intellectual functioning.

Fifty percent of children with an affected parent will inherit the

Huntington's gene and go on to develop the disease. Although the gene

is present from conception, symptoms of Huntington's typically don't

occur until middle age.

With diseases that don't manifest until later in life, most medical

ethicists agree, parents should not make decisions about testing

their child unless the results offer potential medical benefits.

Instead, children should make these choices when they are mature

enough to carefully weigh their options and understand the

implications.

" Allowing parents to make the decision about testing for their

children robs them of their ability to decide for themselves whether

or not they want to know their genetic status, " says Dr. Mark Levine,

chairman of the American Medical Assn.'s Council on Ethical and

Judicial Affairs. In fact, studies have found that adults at risk for

genetic diseases often decline testing.

Testing children could even be psychologically harmful, triggering

feelings of fear and worry. " There's no need to burden children with

things that there's nothing to do about, " Levine says. Parents too

can be affected. Although a negative test result may produce a

tremendous sense of relief, a positive test can elicit overwhelming

anxiety and guilt.

Proponents of testing suggest that, on some level, many children are

aware of their genetic risk of specific conditions, and that testing

can help relieve their concerns. It might also provide the chance to

gradually adjust to, and accept, their risk or, in some cases,

diagnosis.

" The psychological impact of testing has not been well studied, " says

Bradbury, director of the family risk assessment program at

Fox Chase Cancer Center in Philadelphia. She and other researchers

are now beginning to explore such issues. " I think there is potential

psychological risk, " she says. " But it depends on a number of

factors -- the child, the parents, the family. "

I understand the temptation to test. But I would caution parents to

examine what it really has to offer.

The results often aren't as clear-cut as they're perceived to be. In

most cases, the presence or absence of a specific mutation doesn't

guarantee anything. Many girls who inherit one of the so-called

breast cancer genes, for example, remain cancer-free, while others

who don't have the gene go on to develop the disease.

Simply put, " normal " results aren't a guarantee of good health. Most

diseases are acquired during one's lifetime -- not inherited. In

fact, only about 5% to 10% of cancers are inherited genetically; most

are linked to behavioral and lifestyle issues such as smoking and

alcohol.

Perhaps most important, parents must realize that detection doesn't

necessarily lead to a cure. Currently, our ability to treat genetic

diseases lags well behind our ability to identify the genetic changes

that cause them.

When children are young, it's easy to worry about them and hard to

imagine they'll ever be prepared to make difficult choices (mine have

a tough enough time making the easy ones). Although my husband and I

may not agree with all the choices our children make, we do our best

to keep quiet.

We allow our son to sleep in his clothes if he chooses, and we don't

bug our girls about getting their homework done even if they opt to

put it off until the last minute. We're pretty confident that, at

some point, pajamas will begin to look more comfortable to our son,

and the stress of leaving things until the last minute will reform

our daughters. Even if this doesn't happen, these decisions -- along

with the bigger ones in life -- are ultimately theirs to make.

Dr. Ulene is a board-certified specialist in preventive

medicine practicing in Los Angeles.