Friday, January 23, 2009

THE CARDIOMYOPATHIC GENE, MYBPC3 DELETION, IN INDIANS

Last week, I read, first from our NST, then BBC and then studied the article in heart.org, of the deletion of 25-base pair of the MYBPC3 genes. It took awhile for me to refresh my genetics ( my weakest subject in med school ), before I was confident enough to post this blog. I felt that it was important to note this study, by a group of Indian researchers, and published in Nature Genetics, Jan 18th 2009. The MYBPC3 gene is the gene that codes the synthesis of the cardio-myosin bond. A deletion of the 25 base pair, would result in flawed synthesis of the essential protein, and so cardio-myosin weakness and cardiomypathy, heart failure and death from heart failure or ventricular arrhytmias. My concern is that this genetic defect is found in 4% of the Indians especially those from the south - western part of the Indian sub-continent. For some reason ( maybe the caste system ) the northern Indians are spared. Dr Dhandapany and colleagues claim that 400 per 100,000 deaths in South Western Indian is due to heart failure, probaly as a result of this genetic defect. That is alot.
It is important to note that, we are not talking about coronary artery disease here. It is cardiomyopathy, probably dilated and also hypertrophic cardiomyopathy.
In Malaysia, a large propation of our Indians are from southern eastern and also southern western India. Therefore, as cardiologist we must be aware of the present of cardiomyopathy as a result of the defect in the MYBPC3 gene.
The second point that I would like to make is that, I wish that our local cardiac centers of excellence, especially those with public funding, who have the resources, should look into this genetice defects and see if Malaysians ( with our increasing prevalence of inter-racial marriages ), have this same genetic defect. After all, if the prevalence is 4%, a program of genetic counselling may be in order, so that our Malaysians will not have to suffer from heart failure and cardiomyopathy. As I have said in the past, this is what centers of excellence are for.

1 comment:

Allie said...

I saw this article recently too. I am a genetic counsellor and I work in a clinic where we do a lot of genetic testing for hypertrophic cardiomyopathy. It is important to note that there are a number of genes that are related to HCM. We currently test for a panel of 11 genes, which includes the MYBPC3 gene. The interesting aspect of this study is that they found a high prevalence of a deletion in the MYBPC3 gene. The current genetic testing protocol does not generally look at deletions/duplications in these genes. Therefore, we may be missing a lot with our current testing practices...