SNPs for diabetes

The paper:

The finding:

A team of Finnish and US researchers, led by University of Michigan professor Michael Boehnke, found that several single nucleotide polymorphisms (SNPs) around the transcription factor, hepatocyte nuclear factor-4￡ (HNF4A), were associated with diabetes and traits related to the disease.

The surprise:

Previous scrutiny of the variants around HNF4A yielded disappointing results, because the group hadn't looked far enough upstream. Looking at pooled samples of a 10Mb region of chromosome 20, Boehnke's group located variants associated with diabetes about 47kb upstream of the gene, around P2, a newly discovered alternate promoter.

The work ahead:

Boehnke says the next step is to determine if there is an association between type 2 diabetes risk and the variant a person has at each SNP. Boehnke asks: "Are the variants we looked at themselves the ones that might confer risk to type 2 diabetes, or are they proxies for others nearby?"

Broadening horizons:

Though HNF4A shows promise, so far, a meta-analysis shows only a weak association between diabetes and the SNPs around P2. Coauthor Laura Scott, an associate research scientist at the University of Michigan, says shifting away from region-wide or candidate-gene studies to genome-wide association studies could identify more variants. "It will be neat to see where HNF4A comes out across the whole genome, where its place is in the hierarchy of genes that might cause diabetes."