"Human Genetic Variation" is the scientific "breakthrough" of 2007, according to Science magazine. I have a problem with science journalism when science writers misuse the word "breakthrough" but that's topic for another posting [Breakthrough of the Year in Science].
In this thread I want to discuss the actual choice made by Science editors. Elizabeth Pennisi describes the choice in the lead article of this weeks issue [BREAKTHROUGH OF THE YEAR: Human Genetic Variation].
Equipped with faster, cheaper technologies for sequencing DNA and assessing variation in genomes on scales ranging from one to millions of bases, researchers are finding out how truly different we are from one another.There is some truth to this statement. It's true that the details or the amount of genome-wide of variation are being added to the databases. But is it true that we only realized for the first time in 2007 that humans are different from one another?
Of course not. We've known about massive variation in populations since the the 1960's [The Cause of Variation in a Population]. We've been using DNA fingerprints to identify criminals for more than 15 years. Think about it. Would DNA fingerprinting work if we weren't all different from one another at the level of genome sequence?
The unveiling of the human genome almost 7 years ago cast the first faint light on our complete genetic makeup. Since then, each new genome sequenced and each new individual studied has illuminated our genomic landscape in ever more detail. In 2007, researchers came to appreciate the extent to which our genomes differ from person to person and the implications of this variation for deciphering the genetics of complex diseases and personal traits.We're familiar with the writings of Elizabeth Pennisi so it shouldn't come as a big surprise that she makes statements like this. She seems to be remarkably deficient in her knowledge of scientific background and history.
It is simply not true that "In 2007, researchers came to appreciate the extent to which our genomes differ from person to person." Real scientists have known and appreciated that fact for decades. It's part of understanding junk DNA, Neutral Theory, and the importance of random genetic drift.
The true part of the statement is that by mapping more and more specific examples of variation we can do some experiments that we couldn't do before. This is an advance in technology but not an advance in our understanding of the extend of human genetic variation.