Lab Notes : Kissing Cousins

But in a paper in the journal PLoS Biology, Hamish Spencer of New Zealand's University of Otago and Diane Paul of Harvard's Museum of Comparative Zoology argue that the genetic risk to children born of cousin marriages is much less than widely believed.
Risk is in the eye of the beholder, of course. But in 2002 an expert panel convened by the National Society of Genetic Counselors found that the risks of a first-cousin marriage are about 1.7% to 2% above the background risk for congenital defects and 4.4% above background (which is vanishingly low to begin with) for dying in childhood.