Linking gene differences to disease

Now that the human genome is safely stored in databases and we can look up our shared genetic heritage, researchers have turned their attention to the much smaller number of DNA bases that account for our differences. Most importantly, medical researchers are keen to find out how the most significant source of genetic diversity between individuals, the single nucleotide polymorphisms (SNPs), relate to disease susceptibility and drug treatment. Large scale genomic programmes covering entire countries (Iceland and Estonia) were launched to address this connection, but hit problems.

Researchers currently rely on the slow accumulation of SNP information in genomics databases. But single SNPs are not much use, as it is the combination of SNPs inherited together that could yield clues to medically relevant genetic traits. The Ensembl genome browser, a joint project between the European Bioinformatics Institute and the Wellcome Trust Sanger Institute, both at Hinxton, UK, has therefore introduced a new tool allowing researchers to spot the genetic differences that tend to be inherited together. The linkage disequilibrium viewer will make it much easier for medical geneticists to pinpoint candidate SNPs that they may want to investigate for potential links to disease or drug susceptibility. Ensembl team leader Ewan Birney said: ’Now that we have the tools to track variation effectively, we’re much closer to fulfilling the promise of genomics in terms of better ways of diagnosing and treating disease.’

Michael Gross