http://news.bbc.co.uk/2/hi/science/nature/6174510.stm


Humans show big DNA differences


Scientists have shown that the genetic make-up of humans can vary hugely - far more than was previously thought.


[...]

A great many of these variations are in areas of the genome that would not damage our health, Matthew Hurles and colleagues told the journal Nature.

But others are - and can be shown to play a role in a number of disorders.

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This analysis of so-called copy number variation (CNV) has now revealed some startling results.

It would seem the assumption that the DNA of any two humans is 99.9% similar in content and identity no longer holds. The researchers were astonished to locate 1,447 CNVs in nearly 2,900 genes, the starting "templates" written in the DNA that are used by cells to make the proteins which drive our bodies.

This is a huge, hitherto unrecognised, level of variation between one individual and the next.

"Each one of us has a unique pattern of gains and losses of complete sections of DNA," said Matthew Hurles, of the UK's Wellcome Trust Sanger Institute.

"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% of the genome.
"The copy number variation that researchers had seen before was simply the tip of the iceberg, while the bulk lay submerged, undetected. We now appreciate the immense contribution of this phenomenon to genetic differences between individuals."

[...]

As well as aiding the investigation of disease and the development of new drugs, the research will also inform the study of human evolution, which probes genetic variation in modern populations for what it can say about their relationship to ancestral peoples.

Story from BBC NEWS:

http://news.bbc.co.uk/go/pr/fr/-/2/h...re/6174510.stm

Published: 2006/11/23 06:13:50 GMT

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