02-21-2011, 08:30 PM
I think there is a misconception as to why geneticists get involved in history. It is not to rewrite or confirm history, it is to gain a better understanding of the genetics.
Most research is aimed at improvements in forensics or in medicine. In a large mixed city such as New York, the police want to know from any DNA left at a crime scene, 'who are we looking for'. In the absence of a comprehensive genetic database, they will settle on an answer 'someone of southern european descent'. In medicine, in a country such as the UK, the health authorities want to know which parts of the country are at risk of this or that particular disease. The association of genes with origins is driven by those goals, not history, but, in an emerging science, there is much to be learned, in particular, 'what are we looking for?'
The identification of markers which inform us is the key and there are many yet to be discovered. These markers need to be tested against identifiable groups, to see whether they are accurate markers or not. To save on the cost of the tests, the aim is to get at a minimal set of the most informative markers. If you look at too little DNA you may only conclude that the subject is human. If you look at too much, you may only identify an individual, except you don't know who he or she is. Geneticists tend to use historical views to help confirm identification of genetic markers rather than use the genetic markers to determine the past history.
The Peoples of the British Isles project is an offshoot of the Wellcome Trust's study to create a control set for use in medical research. Although the main aim is, for example, to better understand genetic susceptibility to melanoma, the health services want to know which parts of the country are more at risk than others so that they can better target their resources. Although we knew that red haired people with very white skins and freckles are at higher risk than others, many more people are at risk because they carry one copy of the alleles involved but not both copies which allows the trait to be expressed. They want to know where those people live, statistically that is. The easiest way is to categorise people into welsh, irish, scots, southern, central or northern english at a genetic level. Hence you see the sort of maps in fig. 1 on page 6, published in 'Lactase persistence-related genetic variant:population substructure and health outcomes',
http://www.nature.com/ejhg/journal/v17/n...08156a.pdf
If you ever look at the publications for any of the names mentioned in historical studies, eg. Mike Weale, you'll see that their other studies include titles such as, 'Identifying candidate causal variants responsible for altered activity of the ABCB1 multidrug resistance gene.' or 'Strong association of the Saitohin gene Q7 variant with progressive supranuclear palsy.' He's not doing it because he's a historian. He's doing it to see if it works.
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authun
Most research is aimed at improvements in forensics or in medicine. In a large mixed city such as New York, the police want to know from any DNA left at a crime scene, 'who are we looking for'. In the absence of a comprehensive genetic database, they will settle on an answer 'someone of southern european descent'. In medicine, in a country such as the UK, the health authorities want to know which parts of the country are at risk of this or that particular disease. The association of genes with origins is driven by those goals, not history, but, in an emerging science, there is much to be learned, in particular, 'what are we looking for?'
The identification of markers which inform us is the key and there are many yet to be discovered. These markers need to be tested against identifiable groups, to see whether they are accurate markers or not. To save on the cost of the tests, the aim is to get at a minimal set of the most informative markers. If you look at too little DNA you may only conclude that the subject is human. If you look at too much, you may only identify an individual, except you don't know who he or she is. Geneticists tend to use historical views to help confirm identification of genetic markers rather than use the genetic markers to determine the past history.
The Peoples of the British Isles project is an offshoot of the Wellcome Trust's study to create a control set for use in medical research. Although the main aim is, for example, to better understand genetic susceptibility to melanoma, the health services want to know which parts of the country are more at risk than others so that they can better target their resources. Although we knew that red haired people with very white skins and freckles are at higher risk than others, many more people are at risk because they carry one copy of the alleles involved but not both copies which allows the trait to be expressed. They want to know where those people live, statistically that is. The easiest way is to categorise people into welsh, irish, scots, southern, central or northern english at a genetic level. Hence you see the sort of maps in fig. 1 on page 6, published in 'Lactase persistence-related genetic variant:population substructure and health outcomes',
http://www.nature.com/ejhg/journal/v17/n...08156a.pdf
If you ever look at the publications for any of the names mentioned in historical studies, eg. Mike Weale, you'll see that their other studies include titles such as, 'Identifying candidate causal variants responsible for altered activity of the ABCB1 multidrug resistance gene.' or 'Strong association of the Saitohin gene Q7 variant with progressive supranuclear palsy.' He's not doing it because he's a historian. He's doing it to see if it works.
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authun
Harry Amphlett
