Cardiology is clearly on the verge of its most golden era. The lifespan of a woman in the United States in 1900 was 36 years, and is now doubled. We expect this to double again in the next 100 years, but if that happens, we need to do a better job in maintaining cardiovascular health, if we're going to work until we're 160 years old.

At present, 80% of all deaths in the world are due to 20 diseases, with about 300 genes conferring susceptibility to those diseases. Clearly, ongoing genetic research, which is enabling us to identify the function of all these genes, is going to improve out ability to diagnose and treat our patients. For example, just in the last 10 years, we have identified several genetic abnormalities associated with hypertrophic cardiomyopathy, and while we cannot yet use genetic therapy to treat people with this disease, identification of these specific abnormalities does currently have prognostic value.

We have identified all genes for more than 50 organisms, and will soon have complete sequences for the mouse and rat. Our genetic library now contains a total of 11 billion DNA sequences. When we investigate a human gene, we look in the library for a similar DNA sequence. If we find it, and we know the function of that sequence in that organism, we can assume the gene will have a similar function in humans.

Of approximately 1,000 genes known to be related to disease in humans, 18%, including 14,000 known mutations, are associated with cardiovascular diseases such as cardiomyopathies, septal defects, aortic aneurysms, conduction disorders, and arrhythmias. Ideally, we will be able to use this information in a very exciting way. Through normal cell replication, every person receives an entirely new human heart approximately every 3 weeks. Most cells turn over every few days, but with calcification and fibrosis, it can take about 17 days. Each cell has 2 copies of each gene, but needs only one. In the future, for people with cardiovascular disease caused by a genetic defect, we will be able to knock out the abnormal genes, so that in a few days, as only the normal genes replicate, the person will have a completely normal heart.