These are the genes we don’t need – or do we?

Rare human knockouts. Recessive disorders arise when both copies of a causative gene are affected by mutations. These diseases are thought to be a very rare occurrence, but the cumulative impact of these conditions is not known. Population genome sequencing offers the possibility to assess the spectrum and distribution of potentially causative mutations in large groups of individuals. In a recent publication from deCODE published in Nature Genetics, the authors examine the population spectrum of rare human knockouts using the unique genetic data and population structure of the Icelanders. Here is the story about potential candidate genes identified by population genetics. Continue reading

The age of mega-genomics, type 2 diabetes, and protective variants in SLC30A8

Sequence first. There are larger genetic studies but not too many. In a recent study in Nature Genetics, roughly 150,000 individuals were genotyped to assess the importance of rare, disruptive variants in SLC30A8 in type 2 diabetes. This genomic tour de force was made possible by available and curated databases that could be tapped to extract the necessary genetic information. Also, this study highlights some of the surprises that we can expect by mining the human genome for disease-related information. Rare, disruptive variants in SLC30A8 protect against type 2 diabetes. Let’s review why these rare, protective genetic factors might be particularly important for biomedical research and what kind of studies we need to identify them. Continue reading

Genes, patents and the Myriad story

When genes meet the law. Last week, the Supreme Court of the United States of America (SCOTUS) ruled that genes are not patentable, a decision that will be known as the “Myriad Decision”, named after Myriad Genetics, a commercial laboratory that is the single provider for BRCA1/2 testing in breast cancer and ovarian cancer in the United States. For more than a decade, Myriad has had virtually exclusive rights to the genetic analysis of both genes, given a large number of patents surrounding BRCA1/2 analysis. Continue reading

The years of our fathers: paternal age and the rate of de novo mutations

Aging fathers. An increase in risk of aneuploidies, i.e. chromosomal aberrations such as Trisomy 21, is well established with maternal age.  Whether the paternal age also increases the risk for disorders in the offspring had long been disputed. However, a connection between paternal age and autism has been found in recent years. Now a recent study in Nature finds a surprisingly strong correlation on the genetic level… Continue reading

Mutations don’t always cause disease, quite the opposite

A mutation in APP protecting against Alzheimer’s disease. Alzheimer’s disease is one of the leading causes of dementia in the Western world. In rare familial forms of Alzheimer’s disease, variants in the APP gene are well-known to be disease-causing. This led Jonnson and colleagues to search for additional rare variants in the APP gene that might be associated with further cases of Alzheimer’s disease. When they analysed their datasets, they stumbled across an associated APP variant. However, this variant does not increase the risk for Alzheimer’s, it reduces it… Continue reading