Thanks for the ping...very interesting.
"In some Icelanders, the Decode team found, the section runs in the standard direction but in others it is flipped. Looking for any physical consequence, the Decode researchers found that women carrying the flipped or inverted section tend to have slightly more children."
Thanks. I haven't read it in entire yet, but if this study was done in Iceland, even with the Vikings sailing all devil-may-care in the northern Atlantic (until the Little Ice Age hit and put on the brakes), islands tend to concentrate mutations in the population.
It also occurs to me that, if this is at all an old mutation, then the "slightly more children" factor, over generations, would tend to make it a fairly commonplace snip of code. :')