30 Key Genes Linked To Aging Across Species

Credit: University of Michigan SNRE Lab

After wading through 40,000 genes in multiple organisms, a team has narrowed down 30 conserved across species that are associated with aging. 

Trawling through data 

A team of researchers in Zurich began the search with 40,000 genes common to the model organisms C. elegans and zebrafish, as well as mice. They then analysed which of these were especially active in different youth, maturity and 'old age'. 

30 culprits

After large scale statistical modelling the researchers arrived at a pack of 30 genes which were surprisingly conserved across the species. This means these genes were orthologous - coding for a protein product with a similar structure and organisation. 

These genes are conserved from zebrafish to humans

"We looked only for the genes that are conserved in evolution and therefore exist in all organisms, including humans" 

After identifying this group, the team began using mRNA to block gene expression and observe the effect. In nearly half of the genes blocking expression produced a minimal life extension of up to 5%, but there was no apparent negative effect from blocking them. 

One particular gene produced a 25% increase

While altering the majority had a fairly small effect, blocking one specific gene in C. elegans called bcat-1 produced a lifespan extension of up to 25%. What was it associated with? Metabolism of branched chain amino acids, commonly known as BCAAs in the body building world.

What does bcat-1 do?

This gene produces an enzyme that breaks down these 3 branched chain amino acids, all of which are essential for human health. They're absolutely crucial for overall health and replenishing tissue, and are currently used to prevent liver damage as well as being beloved by fitness fanatics. Blocking this gene meant that these 3 amino acids were free to accumulate and remain longer in the tissue at higher concentrations. This apparently had a protective effect. It also increased the amount of time the organisms were healthy, as well as raising mean lifespan.  

Blocking is different to consuming more

After the team had established what the gene function was, they tried feeding the C. elegans subjects more of these branched chain amino acids. While this did have a small longevity promoting effect, it was minimal in comparison to blocking the gene itself. This means while taking more of these molecules may have a small health promoting effect, your body will still break them down quickly. 

Be careful extrapolating to humans

While efforts on model organisms like C. elegans sometimes points us in the right direction, it's much easier to extend the lifespan of smaller organisms.  On a warning note, individuals with branched-chain ketoaciduria also have a deficiency in an enzyme that breaks BCAAs down, but experience severe health effects and a build up of toxic by products. It may be a small modification has some benefits, but that too much is toxic. While consuming more BCAAs has some positive effects such as muscle creation we'll need more human studies to reveal any more information on this gene family and the other 29 genes. 

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