Thursday, September 6, 2007

LRP8 and Familial MI....Ho Hum

This month in the American Journal of Human Genetics we have some interesting publications. Including an association study identifying a gene known as LRP8. So what is LRP8? It is a receptor for bad cholesterol. When bad cholesterol binds this receptor, platelets (the bricks in your blood that build a clot) become sticky making it easier to thrombose (form a clot).

I am interested in this study for several reasons. First, it has been shown that platelets get stick even after ingesting a Big Mac. That's correct. Just one fast food hamburger can theoretically precipitate a heart attack. So naturally we would love to know who. Think Personalized Diet/Nutrigenomics. I wonder if Salugen can hear me now? I still haven't received their "Scientific Data" yet. I will publicize it if they do.

Back to the study. So what was studied is a group called the GeneQuest families of familial MI, the control group was some white men who were given cardiac catheterization and found to have no atherosclerosis burden (OOPS). Well, that control does not mean they did not have atherosclerotic burden, because catheterization cannot identify 30% occluded vessel plaques.

In addition their findings were replicated on an Italian cohort of familial heart attack as well. So why do I say Ho Hum?

Let's see: No Odds Ratio was greater than 1.43 This 43% increase in heart attack and coronary artery disease is still less than the family history risk itself. The only good thing was that this risk persisted even when controlling for plasma total cholesterol levels, triglyceride levels, hypertension, and diabetes, in addition to age and sex.

What is your odds ratio for heart attack if your father had one prior to 65?

The Answer: 5.8 according to Maren Scheuner's article on familial risk for MI.

Do you now see why I say HO HUM about this gene? When will we see the gene card panel for MI??????

The Sherpa Says: Listen to all of this hulabaloo about Ventner's Genome. Even Men's Health magazine says you should bank your parents DNA if they die. What good is all of this if we don't have a key to the map? The map will make no sense! LRP8, APOE4, I could go on and on. What good is a genome map, without a guide? What good is the guide without the studies? Why did you buy the iPOD early, only to have late adopters get it cheaper? For the rebate? Doubtful. This is why primary care physicians are late adopters. If you want to get your genome (and I do) then you better be prepared to find someone who will help you understand it...becasue cliff notes, or Navigenics just won't do. Nor will scarfing down Big Macs....