Do different human groups have significantly different DNA?
All humans have about 100,000 genes (the exact number is still unknown) that transmit heritable traits from parents to children. These genes are encoded in segments of DNA and are almost all contained on the 46 chromosomes in each of our cells. DNA transmits its information through the four different nucleotide bases it contains, which are the “letters” of the genetic code A, C, G, and T. These bases, when read as strings of three-letter “words,” form the blueprints for the molecules that make every part of our bodies function. All the DNA in a human being’s chromosomes make up his or her “genome.” Some of that DNA actually makes up genes and transmits useful information; much of it, however, has no known function. In almost all humans, almost all genes are almost identical. These genes have to be very similar or else the bodies they build wouldn’t work and their owners would die. Some DNA bases and sequences can differ from person to person without changing anything, as they don’t see
