Only one way that genetic marker could have been placed.

In this case, however, the challenge is to find a genetic marker.

Recent studies have been published using an increasing number of genetic markers.

In contrast, studies based on a higher number of genetic markers have found more agreement.

Most learned instead that they shared genetic markers with people of different skin colors.

We're also finding genetic markers in the very areas we were looking for.

But some experts say that genetic markers unique to one group are not known to exist.

No blood test or genetic marker exists to diagnosis the disease.

"The discovery of genetic markers is extremely important," she said.

On the other hand, genetic markers associated with Africans can turn up in people who look entirely white.