Genetic info database

It is increasingly realized that genetic polymorphisms affect our risks for certain diseases or predispose us to toxicity from certain drugs. Examples include BRCA1, the polymorphism predisposing women to breast and ovarian cancer, and DPD deficiency, a defect in the ability to metabolize certain chemotherapy drugs which results in lethal toxicity when they are given. Many other genetic polymorphisms are known, with more discovered every day. In some situation, the knowledge that one may carry such a polymorphism can be very useful.

There exist large databases in which one can trace geneology. Suppose I receive fluorouracil and almost die, and it is proven that I have congenital DPD deficiency. In the genetic info database, I add the fact that I have DPD deficiency. The program knows the inheritance pattern of DPD deficiency and can calculate the odds of carrying the mutation for each of my relatives. My second cousin (whom I do not know) can look herself up and find that she has a 20% chance of being DPD deficient as I am, and so decline to take fluorouracil, or ask to be tested. If she is tested and found not to be DPD deficient, she can add this information to the database under her own name. The risk for DPD of all of our common relatives can then be adjusted.

Such a database relies on two things: that people are truthful and information is accurate.