Mirror extreme BMI phenotypes associated with gene dosage at the chromosome 16p11.2 locus

Underweight and obese phenotypes can both pose health risks. But whereas obesity has been associated with a number of genetic variants, little is known about the genetic basis of underweight. A large-scale screen of data from 28 cytogenetic centres in Europe and North America now shows that being underweight is frequently associated with duplication of a short region on chromosome 16. Continue reading

Novel method to estimate explained variance of GWAS hits reveals large fraction of the missing heritability

Genome-wide association studies (GWAS) are conducted with the promise to discover novel genetic variants associated with diverse traits. For most traits, associated markers individually explain just a modest fraction of the phenotypic variation, but their number can well be in the hundreds. We developed a maximum likelihood method that allows us to infer the distribution of associated variants even when many of them were missed by chance.

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Genome-wide Association Study reveals new HLA-haplotype strongly protective against narcolepsy

We are involved in a Genome-wide Association Study on narcolepsy conducted by Mehdi Tafti’s Group at the University of Lausanne. In brief, we identified a haplotype in the HLA-region that is strongly protective against narcolepsy. More than 10% of HLA-positive controls carry this DRB1*1301-DQB1*0603 haplotype, which was found in virtually no narcoleptic cases. The research findings were published in Nature Genetics.