Humans Have Multiple Copies of Some Key Genes

Scientists have discovered a dramatic variation in the genetic make-up of humans that could lead to a fundamental reappraisal of what causes incurable diseases and could provide a greater understanding of mankind.

The studies published today have found that instead of having just two copies of each gene - one from each parent - people can carry many copies, but just how many can vary between one person and the next.

One of the real surprises of these results was just how much of our DNA varies in copy number. We estimate this to be at least 12 per cent of the genome - that has never been shown before. They found that 2,900 genes could vary in the number of copies possessed by the individuals.

The findings mean that instead of humanity being 99.9 per cent identical, as previously believed, we are at least 10 times more different between one another than once thought.

Another implication of the finding is that we are more different to our closest living relative, the chimpanzee, than previously assumed from earlier studies. Instead of being 99 per cent similar, we are more likely to be about 96 per cent similar.

via The Independent