These mutations reduce the enzyme's ability to attach biotin to carboxylases and histones.
Surprisingly, minor mutations reduce fitness just as much as those with larger effects, because they rise to higher frequency in a mutation selection balance.
Now, suppose that deleterious mutations reduce survival below this optimal value.
This mutation reduces body weight in females by 26 to 32%, but the effect is still greater in homozygous males, by about 42-43%.
The researchers were able to conclusively determine that the mutation of this regulatory protein reduced Gal expression.
In constant conditions, the mutation significantly reduced the number of rhythmic antennal pairs for both reporters.
Scattered throughout the genome, these mutations reduce a cell's ability to repair DNA.
If a new mutation reduces their susceptibility to an antibiotic, these individuals are more likely to survive when next confronted with that antibiotic.
It is not thought that the mutation causes a complete loss of function of the protein but rather only slightly reduces the transporter's activity.
Single mutations of any of these four residues reduce IN enzymatic activity.