Spring of 2000 found molecular biologists placing dollar bets,
trying to predict the number of genes that would be found in the human genome when the sequence of its DNA nucleotides was completed. Estimates at the time ranged as high as 153,000. After all, many said, humans make some 90,000 different types of protein, so we should have at least as many genes to encode them. And given our complexity, we ought to have a bigger genetic assortment than the 1,000-cell roundworm, Caenorhabditis elegans, which has a 19,500-gene complement, or corn, with its 40,000 genes.
This article was originally published with the title The Alternative Genome.