1. DNA is obtained from the bone marrow cells of patients with two types of leukemia.

2. The DNA is exposed to biochips containing all known human genes.

3. High-speed computer programs examine the biochips and identify any SNPs, or single nucleotide polymorphisms.

4. The SNP profiles from each type of leukemia patient are examined. Leukemia 1 exhibits a different SNP than leukemia 2. Thus, the two types of leukemia are associated with two different gene changes.

To what extent are you your genes? Scientists fight about this question, and no one really knows the answer. It is clear that much of what each of us is like is strongly affected by our genetic makeup. Researchers have proven beyond any real dispute that intelligence and major personality traits like aggressiveness and inquisitiveness are about 80% heritable (that is, 80% of the variation in these traits reflects variation in genes).

Your SNP profile will reflect all of this variation, a table of contents of your chromosomes, a molecular

window to who you are. When millions of such snp profiles have been gathered over the coming years, computers will be able to identify other individuals with profiles like yours, and, by examining health records, standard personality tests, and the like, correlate parts of your profile with particular traits. Even behavioral characteristics involving many genes, which until now have been thought too complex to ever analyze, cannot resist a determined assault by a computer comparing SNP profiles.