Bipolar disorder is somewhat related to schizophrenia but classified as a distinct disorder
in which we have varying moods from happy to sad, manic and depressive. It also affects
almost 1% of the population, which I think is a profound statistic. Again, family aggregation
and twin studies strongly suggest that there’s a genetic component. We can see some statistics
over here again for lambda, relatively high lambda values also indicating a genetic component
to bipolar disorders. These are things to keep your eyes on as you move forward in your practice
for the genetics that might be coming out behind them. Keep your eyes on the current research.
Another condition that we are aware there’s genetic component to, also a serious multifactorial
disease because we have so many potential places for genetic mutations as well as
environmental components. But you can clearly see in this graphic that we have concordance rates
for monozygotic and dizygotic twins that differ substantially from each other even though
they’re fairly small values apparently. We still see like 15-fold, 2-fold increase, 3-fold increase
of risk for related individuals. Again, a genetic component is there. We don’t yet know where it is.
But if you look at the process of formation of a thrombus or plaques in coronary artery disease
and closing of the vessels, there are so many steps along the way which naturally are going to be
regulated by many different genes including those involved in development of the calcification itself.
The inflammatory response that goes on in every single protein involved could have a mutation.
Thus, this could be a very, very complex disorder but we are seeing clearly that there is some
hereditary component. Although there is also, as I’m sure you’re aware, a large environmental situation too.
It’s pretty hard to sort out the environmental predisposition from the genetic predisposition
when we consider the diet and physical activity and general systemic inflammation, perhaps from eating
too many refined sugars and such as well as smoking. All of these environmental predispositions
can have an impact on the expression of all of the genes that could possibly involve.
I guess that you get the picture that these multifactorial disorders really, truly can be
multi super factorial disorders that are going to take some time to tease apart from each other.