The breakthrough of this year has to do with humans, genomes, and genetics. But it is not about THE human genome (as if there were only one!). Instead, it is about your particular genome, or mine, and what it can tell us about our backgrounds and the quality of our futures.
A number of studies in the past year have led to a new appreciation of human genetic diversity. As soon as genomes are looked at individually, important differences appear: Different single-nucleotide polymorphisms are scattered throughout, and singular combinations of particular genes forming haplotypes emerge. A flood of scans for these variations across the genome has pointed to genes involved in behavioral traits as well as to those that may foretell deferred disease liability. And more extensive structural variations, such as additions, deletions, repeat sequences, and stretches of "backwards" DNA, turn out to be more prevalent than had been recognized. These too are increasingly being associated with disease risks.