Genes that affect diseases and other traits may be scattered across genome – Scope (blog)

Biomedical researchers tend to envision genes for traits from height to Alzheimers disease as being clustered in a limited number of pathways.

Two assumptions have guided this perspective: that specific traits or diseases are influenced by a few dozen genes andthat this limited menu of genes tends to be governed bymolecular pathways known to be associated with the disease.

For example, researchers might look for genes promoting diabetes in molecular pathways associated with sugar metabolism. Similarly, a hunt for genes that increase the risk for Alzheimers would focus on pathways active in the brain.

But while those assumptions make intuitive sense, Jonathan Pritchard, PhD, professor of genetics and of biology, said he has found that data dont always agree.

Recently, Pritchard and colleagues (shown above) published apaper in Cellsuggesting that the bulk of the inheritance of complex traits comes not from those few dozen core genes but from thousands of gene variants scattered across the genome. Graduate student Evan Boyle and postdoctoral scholar Yang Li, PhD, share lead authorship.

As Ireported in anews release:

The gene activity of cells is so broadly networked that virtually any gene can influence disease, the researchers found. As a result, most of the heritability of diseases is due not to a handful of core genes, but to tiny contributions from vast numbers of peripheral genes that function outside disease pathways.

Any given trait, it seems, is not controlled by a small set of genes. Instead, nearly every gene in the genome influences everything about us. The effects may be tiny, but they add up.

Its an interesting perspective, one that is sure to spur a host of inquiries.

Previously:New technique offers glimpse at human evolution in action,Genetics: A look back at the first 100 years,Computing our evolution Photo by Steve Fisch

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Genes that affect diseases and other traits may be scattered across genome - Scope (blog)