The International Tandem Repeat Consortium (ITRC) has announced the public launch of a powerful new genetic database aimed at generating a new focus in genetic research.
The human genome sequence differs between individuals at millions of locations, and this variation is one the factors that makes people different: for example, more or less susceptible to various diseases. Despite the recent avalanche of DNA sequence information from humans and many other genomes, most scientists restrict their analyses to just one type of variation, the single nucleotide polymorphism (SNP).
However, other types of genetic variation make as great a contribution to human health and variety as SNPs. In particular, tandem repeats are extremely common and often influence gene function and disease (eg diabetes or depression). They comprise repeat copies of a sequence of bases; for example, a simple sequence such as CA or perhaps a more complex one such as CATAGATGGT. These vary in the number of copies occurring on certain chromosomes; hence, one tandem repeat polymorphism may have several versions of a particular repeat.
The ITRC database will provide powerful maps of genetic variation and gene regulatory elements in genomes, based on these tandem repeats. "The consortium's major contribution will be the realisation that we have to look at tandem repeats in addition to SNPs if we are to fully understand the contribution genetic variation to human health, Our project will, for the first time, provide a standardised framework for studies of tandem repeats," said the project coordinator Dr Gerome Breen.
The main targets of the ITRC are to characterise hundreds of thousands of tandem repeats in diverse organisms, release these data and integrate the information in existing genome databases. "This project will help us create a far more powerful database of human genetic variation than would be possible using SNPs alone, and benefits will extend to researchers working with organisms from bacteria through to the giant panda," said organising committee chairman Professor David Collier.