Genetic tests available online are a waste of time and money

At least three articles today indicate that experts around the world are finding genetic tests available through the Internet are a waste of time and money. Here are the three I sampled:

1. From Australia: Genetic testing over the net a waste of money says experts

. . .people who buy genetic tests from private companies are usually wasting their money. The specialists say the genome-wide scans on offer will provide little meaningful information because the science is still too preliminary.

They also believe the scans can mislead people into becoming either over-anxious about being labelled "high risk", or over-confident that they are at low risk of a particular disease.

Scientists have already linked a number of genes to common diseases but these interact in a complex manner and their ultimate effect is influenced by environmental factors in ways that are as yet not clearly understood.

2. From the U.S.: DNA ancestry testing leaves some in doubt

Henry Louis Gates Jr., whose PBS special "African American Lives" explores the ancestry of famous African Americans using DNA testing, has done more than anyone to help popularize such tests and companies that offer them. But recently this Harvard professor has become one of the industry's critics.

Gates says his concerns date back to 2000, when a company told him his maternal ancestry could most likely be traced back to Egypt, probably to the Nubian ethnic group. Five years later, however, a test by a second company startled him. It concluded that his maternal ancestors were not Nubian or even African, but most likely European. One of the most controversial issues is the ability of the tests to determine the country or the ethnic group of origin for African Americans or American Indians.

In an editorial in Science magazine in October, a number of scientists and scholars said companies might not be fully explaining the limitations of genetic testing, or what results actually mean. The authors said limited information in the databases used to compare DNA results might lead people to draw the wrong conclusions or to misinterpret results. The tests trace only a few of a customer's ancestors and cannot tell exactly where ancestors might have lived, or the specific ethnic group to which they might have belonged. And the databases of many companies are not only small - they're also proprietary, making it hard to verify results.

Mitochondrial and Y-chromosome tests [used for "ancestry testing] combined reveal information pertaining to just 1 percent of a person's DNA. Tests that examine the DNA contribution of both parents . . . are the most controversial because many scientists say there isn't enough data yet to get accurate results.

Edward Ball, author of The Genetic Strand (Simon & Schuster), sent labeled hair samples of various family members to various companies for DNA testing. The first tests found that some of the family's DNA was American Indian. Another company found African genes in his family tree, but no Indian ones. Then he was told by one of the various experts he consulted that the DNA most likely originated in Northern Europe. Ball didn't know what to believe.

It's not that the tests are wrong, scientists say. Most companies use the same methods and, in some cases, the same labs to extract DNA from samples. But even the largest databases have only a few thousand records in them, and some areas and populations are sampled more than others. Most companies obtain data from information published in publicly available research papers; few collect samples themselves. Scientists emphasize that much of this data was gathered for other purposes and was never intended to be used for personal genealogical testing.

"What this all means is that you can't take one of these tests and go off and say you're this or that," Gates said. "Somewhere down the road, the results could change and you might have another group of people who might also be your genetic cousins."

3. And from the U.K.: Home genetic testing kits a waste of money

The tests, most of which are available over the internet, often cost more than £500 and the market for them is expanding. They have featured on television programmes in which celebrities undergo genetic testing to discover their risk of potentially fatal diseases. They claim to calculate the risk of contracting diseases including Alzheimer's, cancer and diabetes. However, the wrong genes are often tested, which makes the results almost meaningless, according to scientists.

The Human Genetics Commission, a Government advisory body, will call next week for tighter regulation of the tests, including rules that the claims must be independently evaluated before they can be sold to the public.

People worried by test results have taken up appointments at National Health Service clinics that could have been better used by others.

There are many more versions and releases of these stories. Have you decided to save your money yet?

Marie Godfrey, PhD





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