• Question: If we eradicate all disease from everyone and make genetics more similar, wouldn't that make people less unique?

    Asked by aledxmas18 to Tomas, Reka, Omar, Oliver, Judith, Ed, Aoife, Alice on 22 Dec 2018.
    • Photo: Tomas Fitzgerald

      Tomas Fitzgerald answered on 22 Dec 2018:

      I think there are a few questions posed here.

      Eradicating all disease is a laudable goal and understanding the genetic basis for disease is an important part of this effort. However i think it is extremely unlikely that this would be achieved by making people more genetically similar. On the contrary a high degree of genetic diversity in a population gives greater robustness against disease. Biology is a complex system and there are normally several ways by which it can compensate for any given problem (multiple pathways that do similar jobs and can take over if one fails).

      The question, “if people become more genetically similar would they become less unique?” is very interesting, I think this is true to some degree, i.e. if all peoples genome were exactly the same, they would likely look rather similar and have similar baseline susceptibility to certain diseases etc, but there is proportion of phenotypic variability (peoples characteristics) that have an environmental component. This is the so called G x E (Genetic times Environment) effect and different genes (or variants in genes) are influenced more or less by environmental changes (some genes/variants are effected more than others by a change in environment). This is an active area of research, but is rater hard to study in humans (you can not control the environment in humans).

    • Photo: Judith Sleeman

      Judith Sleeman answered on 26 Dec 2018:

      There would still be plenty of differences, I think, but this is really a question that we need to answer together as a society. There are plenty of genetic diseases that I can’t imagine anyone wanting to keep, but where do we want to draw the line between ‘diversity’ and ‘in need of a cure’?

    • Photo: Edward Morrison

      Edward Morrison answered on 28 Dec 2018:

      I don’t see that eradicating disease would make people more similar. If anything it would have the opposite effect. Disease is a potent agent of natural selection which acts to reduce the genetic diversity in a population.

      Interestingly, humans are very genetically non-diverse population compared to many animals. This is because modern humans originated from an African population only a few hundred thousand years ago and haven’t changed much since then. We do see some differences since then like skin colour, but not many compared to most animals.