Blood disease caused by SNP-built promoter

Single nucleotide polymorphisms (SNPs) can cause genetic disease by creating entirely new transcriptional elements, according to a report in this week's Science. The study shows that a SNP in noncoding DNA near the alpha globin gene cluster creates a gain-of-function promoter-like element that interferes with normal globin expression, causing the blood disease alpha thalassemia. Similar mechanisms could be at the heart of other genetic disorders, the authors suggest. "It's really a novel mechanism by which a disease can be created genetically," said Gerd Blobel of the University of Pennsylvania in Philadelphia, who was not involved in the study. In alpha thalassemia, reduced expression of any of four alpha globin genes causes anemia and red blood cell abnormalities. Many different mechanisms have been shown to underlie this down-regulation.Led by Marco De Gobbi of John Radcliffe Hospital in Oxford, UK, and Vip Viprakasit of Mahidol University in Bangkok, Thailand, the...