At the metaphase to anaphase transition, APC/C bound to Cdc20 targets cyclins A /B and securin for degradation.

TLS Online TPP Program

#Id: 2232

#Section 3: Genetics, Cellular and Molecular Biology

De novo genes -New Genes in organisms ranging from yeast to humans that did indeed originate from noncoding DNA,

TLS Online TPP Program

#Id: 8961

#Section 3: Genetics, Cellular and Molecular Biology

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

TLS Online TPP Program

#Id: 8962

#Section 3: Genetics, Cellular and Molecular Biology

Fate of duplicate gene 

TLS Online TPP Program

#Id: 8963

#Section 3: Genetics, Cellular and Molecular Biology

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

#Section 3: Genetics, Cellular and Molecular Biology

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

TLS Online TPP Program

#Id: 8960

#Section 3: Genetics, Cellular and Molecular Biology

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.