Human v Chimp
              Chromosome 2

Robertsonian fusion of ape chromosomes in Homo

    Humans have 2n=46 chromosomes, as compared with 2n=48 in our closest relatives, the Great Apes (Chimpanzee, Gorillas, and Orangutans). Whereas Chromosome 2 is a single, large metacentric in humans, the other apes have two smaller, sub-telocentric chromosomes. Comparison of Giemsa banding patterns allows these chromosomes to be aligned, and shows that the ape telocentrics have undergone an end-to-end Robertsonian  fusion to form a single larger metacentric in human evolution. The gene contents of chimp and human chromosomes are substantially identical. Molecular inspection of the area near the human 2q1.3~1.4 region shows telomere-like DNA sequences from the chimp chromosome, as predicted.

Figure & text material ©2012 by Steven M. Carr