There haven't actually been many new ideas in epidemiology
in the last 30 years.
And little thought has been given to explaining exactly how different
environments exert their effect and how they can interact with genes.
But that is changing.
And in the last few years this has
actually become one of the hottest areas in biology.
It's got hot because of new techniques.
And one of these is called Mendelian Randomization, or MR for short.
And MR uses our knowledge of human genes
to pinpoint how the environment and our lifestyle choices affect health.
And last week I mentioned that, some genes are protectors.
They protect your health.
Well, MR simply involves finding out whether it matters to people
if they have good or bad versions of genes for a trait.
And it can clear up all sorts of conflicted epidemiology.
So for years people thought that
raising high-density lipoproteins, so-called good cholesterol,
would protect them from heart attack.
But a large trial of a drug that raises
good cholesterol published in 2012 saw no such benefit.
Now an MR could have saved them the expense.
There's a 2012 computer study using records of
170,000 people that participated in other studies from the
people with gene variants causing high or low levels
of good cholesterol had the same heart attack risk.