37. William Hamilton’s worries about the future of the human genome

Posted by T.T. and P.T. in May 2020

William D. Hamilton (1936-2000) was a significant evolutionary biologist who received the Kyoto Prize in 1993.  He gave much thought to the future of the human genome and, in particular, he was seriously worried about the progressive degradation of humankind in the distant future due to the accumulation of deleterious mutations. Curiously, many evolutionary biologists at that time did not think this was a serious possibility and, therefore he was sometimes regarded as a pessimist.

A genome which characterizes a species is not perfectly stable but instead it varies through a series of mutations as it passes from one generation to the next. Most mutations cause adverse effects on the survival of the specie, but they are mostly removed by natural selection in the wild environment. However, modern medicine tends to keep alive those humans having deleterious mutations, so that the process of natural selection is weekend or even eliminated. Thus, by the accumulation of deleterious mutations, degradation of humankind can indeed occur after many generations, as Hamilton had warned.

Recently, another biologist, Gert Korthof, investigated Hamilton’s arguments on the degradation of the human genome in the future, and he wrote an extensive review, now available  in a website entitled William Hamilton’s worries about the future of the human genome (first published 2011, updated 2017). He discussed the particular problem posed by Hamilton, and he searched for possible solutions based on the use of modern technologies considering many detail. finally, he concluded that we cannot correct the accumulation of deleterious mutations by technological fixes.

Korthof’s conclusion states that the continual advances in medical care aimed at maintaining the welfare of present humans inevitably undermines the welfare of  future humans due to the accumulation of deleterious mutations. If we genuinely hope to gift a healthy genome to future humans, we will have to make sacrifices in our lives to the same extent as occurs by natural selection. In order to achieve that, present humans should be purely altruistic, ‘as a lover who sacrifices their own life to save their beloved’.

It is not only in the accumulation of deleterious mutations that the fate of future humans may be adversely influenced by the activities of present humans. Indeed, although it is mostly not acknowledged by present people, their culturally achieved welfare is often gained at the cost of future people.

Our humankind is now massively challenged by the dilemma of needing to choose either to benefit all individuals or whole generations in the future.