Over at Genetic Future Dr. Daniel MacArthur has a measured response to a Nature commentary by David Goldstein, Growth of genome screening needs debate. As Dr. MacArthur notes an excessive portion of Goldstein’s piece is taken up with inferences derived from assuming that the model of rare variants causing most diseases is correct, when that is an issue currently in scientific contention (and this is a debate where Goldstein is a primary player on one side). But the last two paragraphs of the piece is where the real action is, no matter the details of genetic architecture of diseases:

One potential problem with this is that numerous genetic risk factors will have diverse and unexpected effects — sometimes causing disease, sometimes being harmless and sometimes perhaps being associated with behaviours or characteristics that society deems positive. Even for simpler Mendelian diseases, up to 30% of the mutations originally termed pathogenic have turned out to be apparently harmless…Wholesale elimination of variants associated with disease could end up influencing unexpected traits — increasing the vulnerability of populations to infectious diseases, for instance, or depleting people’s creativity.

There are no clear-cut answers to the questions of what should be screened ...