Two organizer proteins, inhibit Wnt proteins during gastrulation Tiki and Notum

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#Id: 8960

#Unit 11. Evolution and Behavior

Duplicate gene and its parental copy can subfunctionalize so that each carries out only some of the roles that the ancestral gene performed. 

Ex- a duplicate of the β-hemoglobin locus is expressed in the fetus. 

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#Id: 8961

#Unit 11. Evolution and Behavior

No matter how it is born, a new gene starts its life as a single copy in the population.

As with any new mutation, by far the most likely outcome is that it will be lost by random drift or selection over the next few generations

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#Id: 8962

#Unit 11. Evolution and Behavior

Fate of duplicate gene 

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#Id: 8963

#Unit 11. Evolution and Behavior

If the duplicate is redundant and does not provide a fitness benefit, it will be lost by deletion or the accumulation of loss of-function mutations.

A second fate is that a duplicate can simply retain its original function.

TLS Online TPP Program

#Id: 8964

#Unit 11. Evolution and Behavior

A third fate that can befall a duplicated gene is neofunctionalization. Here the duplicate evolves a novel biological function. 

TLS Online TPP Program

#Id: 8965

#Unit 11. Evolution and Behavior

Most protein-encoding genes, the synonymous rate of change is considerably higher than the nonsynonymous rate because synonymous mutations are tolerated by natural selection