Đồng hành lý tưởng để tập trung vào IELTS cuốn sách này giúp học sinh phát triển các kỹ năng cần thiết cho kỳ thi IELTS. Tạo động lực cho học sinh của bạn để phụ trách việc học của mình | MODULE APPEARANCES eyes black and brown light coloured eyes blue and grey or hazel eyes greenish-brown - with 97 certainty. E DNAPrint is now applying exactly the same technique to hair colour identifying possible genes and looking for SNPs. Representatives say they have made some headway and can classify people into one of three groups - blonde brown or black-haired - with some accuracy from their DNA alone. F Back in Britain the Forensic Science Service has also been pursuing the genetic basis of facial features. A few years ago it helped fund a major project carried out by scientists at University College London UCL . Over several months an exhibit at a London museum invited visitors to leave DNA samples and have their faces scanned using 3D surface mapping. About 600 people volunteered. The UCL researchers tried to break down this data on overall facial shape into distinct features such as nose curvature or chin clefts and correlate them to DNA sequences. But they made little progress. Just as with eye colour there is no one gene for a big nose so the enormous complexity of the task defeated the researchers. When the lead scientist retired the project was wound down without drawing any firm conclusions. G But the idea of finding genes for facial features isn t dead. Many of the genes involved are common to most mammals. So a gene for a large jaw in mice for example might very well be found in humans too. One promising project has found that mice show significant variation in jaw shape and size and has begun to unravel the genetics behind the variation. Project leader Chris Klingenberg of the University of Konstanz in Germany cautions that as with humans the genetics controlling jaw shape in mice is horribly complicated but the project is making some progress. In one study of 535 mice it has identified genes for jaw shape jaw size and jaw symmetry and found two basic patterns resulting from the combination of these genes. H The UK-based human rights group known
