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GENE Duplication for Evolutionary Mechanisms

Gene duplication is an important evolutionary mechanism and, as result , many cases are known where species has two nearly identical genes.ySuppose there are two genes, A and B , that specify production of the same enzyme. An abnormal phenotype results only if an individual does not make any of that enzyme. What ratio of normal vs abnormal progeny would result from a mating between two parents of the genotype AaBb , where A and B represent alleles that specify production of the enzyme, and a and b are alleles that do not.

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The ratio of normal to abnormal phenotypes in this question depends upon the number of offspring that are homozygous for both defective alleles of the duplicated gene. These have been designated a and b, so an abnormal phenotype with no enzyme production would have the genotype abab. In other words, the individual has to have ...

Solution Summary

The expert determines why gene duplication is an important evolutionary mechanisms. Abnormal phenotype results for enzymes are determined.