DIVERSITY IS DESTINY: View on Genetics

DIVERSITY IS DESTINY: View on Genetics

Biology is a science that deals with variations. There is no one perfect type of a species. Diversity, in this sense, is not just something to aim at but something necessary for a population to flourish. The idea that natural selection works only on mutations is a deeply misleading oversimplification. It is much more likely to alter the proportions of an already existing mixture of genes. What is more, game theory shows that the balance of advantage will shift as a result of the shift in a gene’s frequency.

This is especially true of the genes which can influence human behaviour and emotional predispositions. Not only is the chain of causation from gene expression to behaviour unimaginably complex, but it is also profoundly affected by outside circumstances. Identical twins, who share the same DNA, are not identical people, because they cannot entirely share the same life and experiences.

Using a data set of nearly half a million people, of whom 27,000 reported same-sex contact, researchers found – in their own words – “In aggregate, all tested genetic variants … do not allow meaningful prediction of an individual’s sexual behaviour”. There are five loci which appear to have a measurable, though far from decisive, influence on sexual preference. Some are also involved with the sense of smell, and one is associated with male pattern baldness.

This leads to perhaps the most interesting feature of the research: it not only shows that there is no clear genetic cause for same-sex attraction, but that the attraction itself does not form a coherent whole. Some of the genetic variations weakly associated with same-sex behaviour are different in men and women. In place of the old idea that there might be a single cause for a single pattern of behaviour, there is now an understanding of multiple causes for varying patterns of behaviour. In place of a single scale of sexual attraction as posited by Kinsey, in which desire for the same sex and opposite sex are linked so that more of one means less of the other, the researchers suggest that these are independent variables. Diversity is good in itself and humans are more – much more – than the sum of their genes.