“A fantastic resource for looking at human population genetics and disease gene susceptibility in a way that has just not been really possible until now.” This is how James Scott, professor of molecular medicine at Hammersmith Hospital in London, describes the availability of the complete sequence of chromosome 22 announced in this issue of Nature.
Scott has pioneered the field of messenger RNA editing, and has mapped the genes relevant to his research into cardiovascular disease to chromosome 22. Benefiting from the early release of sequence data from the public Human Genome Project, Scott has already identified seven new genes at the locus, and is now working on their function and organization.
“We could not have done this work without the chromosome 22 data,” says Scott, who welcomes the end to the long delays in searching for genes using positional cloning, which has been made obsolete by the availability of the complete sequence.
Single-nucleotide polymorphisms and linkage disequilibrium studies will make it possible to study the role of genes in heart disease at the level of individuals and populations, he says. A badly working chromosome 22 is also responsible for the congenital heart disease Di George syndrome, which is caused by the loss of part of the chromosome, 22q11.
Genes linked to schizophrenia, a severe mental illness that affects around one in every 100 people worldwide, also sit somewhere on the chromosome. With the full sequence now openly available, it is unlikely to take long to track them down.