Chapter 10, Problem 21P

Chimpanzees have a set of hemoglobin genes very similar to the set in humans that was shown in Fig. 10.11. For example, the genomes of both species have α1, α2, β, Gγ, Aγ, δ, ε, and ζ genes.

a.	Of the human and chimpanzee hemoglobin genes, which would be considered homologous? Which paralogous? Which orthologous?
b.	When comparing genomes, geneticists would usually like to know which genes are the most likely to perform similar if not identical functions in different species. This determination can be somewhat complicated in the case of gene families. Would paralogous genes or orthologous genes be more likely to be functionally equivalent? Explain.
c.	Which gene would have the greatest degree of nucleotide similarity to the human β gene: the chimpanzee β gene, or the human γ gene? Explain.
d.	Rationalize the pattern of hemoglobin genes in the two species with the existence of duplication and divergence events among the hemoglobin genes depicted in Fig. 10.12.