Each word is written in letters called bases, or nucleotides. Instead of being written on flat pages, genomes are written on long chains of sugars and phosphates called DNA molecules. This pairing property permits a single strand of DNA to assemble, under appropriate conditions, the complementary strand needed to make a complete chromosome, in an act known as replication. In practice, the pro-cess is somewhat more complicated. Almost everything in the human body is either made of or made by proteins.
Every protein is a translated gene.
The human genome contains an as yet undetermined number of genes, presumably 60,000-80,000, though some estimates run as high as 100,000 genes in all. Many of the names are well known, if not always for their contributions to biology. Rosalind Franklin was studying the structure of coal for the British government. Josef Mengele was torturing twins at Auschwitz, ostensibly in the name of science. Claude Shannon was at home in New Jersey, ruminating on the notion that information and entropy are opposite sides of a single coin, both intimately connected with energy.