Another Example of a Human Genetic Variant that Lowers Blood Lipids and thus Reduces Heart Disease Risk
In recent years researchers have discovered a couple of human gene variants that dramatically reduce blood lipid levels, in ANGPTL4 and ASGR1, which in turn reduces the risk of cardiovascular disease by slowing the development of atherosclerosis. The atherosclerotic lesions that form in blood vessel walls are seeded by oxidatively damaged blood lipids, and so lower lipid levels mean less seeding, all other things being equal. The research here presents another such gene variant, though by the sound of it one that has a lesser effect and isn't as widespread across populations.
A genetic variant that protects the heart against cardiovascular disease has been discovered in an isolated Greek population, who are known to live long and healthy lives despite having a diet rich in animal fat. In Mylopotamos in northern Crete the population are unusual as they have a diet that is rich in animal fat and should cause health complications, yet they have good health and live to an old age. In an attempt to solve the puzzle, scientists made a genetic portrait of the population by sequencing the entire genome of 250 individuals to get an in-depth view. This was the first time Mylopotamos villagers had their whole genome sequenced. The team then used the results to give a more detailed view of approximately 3,200 people for whom previous genetic information was known.
Scientists discovered a new genetic variant that was not previously known to have cardioprotective qualities. The variant, rs145556679, was associated with lower levels of both 'bad' natural fats - triglycerides - and 'bad' cholesterol - very low density lipoprotein cholesterol (VLDL). These factors lower the risk of cardiovascular disease. The cardioprotective variant may be almost unique to the Mylopotamos population. rs145556679 resides within an intron of the Down syndrome cell adhesion molecule like 1 (DSCAML1) gene, which is involved in cell adhesion in neuronal processes and is expressed in heart, liver, pancreas, skeletal muscle, kidney and brain. The genome sequencing results of a few thousand Europeans has only revealed one copy of this variant in a single individual in Tuscany, Italy. A separate variant in the same gene has also been found to be associated with lower levels of triglycerides in the Amish founder population in the United States.