ScienceDaily.com reports on an article on DNA testing to be published in the prestigious journal, Science. Its warnings on the limitations and misapplications of DNA testing have implications for the DNA attacks on the Book of Mormon. Some critics rail against the Book of Mormon because DNA testing of modern Native Americans does not appear to point to the Middle East as the primary ancient source of early Americans. Such attacks rely on outdated and overly simplistic assumptions that are not supported by the text itself.
Excerpts from the summary about the Science report follow:
Genetic Ancestral Testing Cannot Deliver On Its Promise, Study Warns
ScienceDaily (Oct. 20, 2007) — For many Americans, the potential to track one’s DNA to a specific country, region or tribe with a take-home kit is highly alluring. But while the popularity of genetic ancestry testing is rising – particularly among African Americans – the technology is flawed and could spawn unwelcome societal consequences, according to researchers from several institutions nationwide, including the University of California, Berkeley.
“Because race has such profound social, political and economic consequences, we should be wary of allowing the concept to be redefined in a way that obscures its historical roots and disconnects from its cultural and socioeconomic context,” says the article to be published in the journal Science.
The article recommends that the American Society of Human Genetics and other genetic and anthropological associations develop policy statements that make clear the limitations and potential dangers of genetic ancestry testing.
Some of the tests’ limitations identified by Bolnick and her co-authors include:
- Most tests trace only a few of your ancestors and a small portion of your DNA,
- Tests are unlikely to identify all of the groups or locations around the world where a test-taker’s relatives are found,
- Tests may report false negatives or false positives,
- Limited sample databases mean test results are subject to misinterpretation,
- There is no clear connection between DNA and racial/ethnic identity,
- Tests cannot determine exactly where ancestors lived or what ethnic identity they held. . . .
“While some companies carefully explain what genetic ancestry tests can and cannot tell a test-taker, other companies provide less information about the limitations and assumptions underlying the tests,” said Deborah Bolnick, assistant professor of anthropology at the University of Texas and lead author of the article.
For example, there are mitochondrial DNA tests, which trace the mother’s lineage, and Y-chromosome tests which track paternal ancestry. The test-taker swipes the saliva inside his or her cheek, and sends the swab to the lab. The DNA is extracted and compared to samples from a reference database of haplotypes – a set of inherited, linked genetic markers – to see if there’s a match.
Because these tests trace only one bloodline, however, they exclude most ancestors. Moreover, they cannot pinpoint where these ancestors lived. “Each test examines less that one percent of the test-taker’s DNA and sheds light on only one ancestor each generation,” the study says. . . .
Publication date in Science, October 18, 2007.
These warnings about the limitations of DNA testing have been made by LDS researchers for some time. Some unqualified critics have twisted such warnings to suggest that they were attacks on the scientific quality of DNA work itself. Far from it. Real science requires constant caution and consideration of the assumptions being made, the limitations of a method, and the range of what can and cannot be determined from any given experiment. And when we apply that kind of scientific rigor to DNA testing and the Book of Mormon, we have to conclude that it is simply unreasonable to expect to find definitive traces of Lehi’s or Sariah’s unknown genetic haplotypes among modern Native Americans 2600 years later, when they may have represented an easily lost drop in the bucket of incoming DNA in the ancient Americas.