Is it possible to eliminate a recessive deleterious allele

The specific case of heterozygote advantage due to a single locus is known as overdominance. Will allele frequencies remain constant generation after generation in a population? When a population is in Hardy-Weinberg equilibrium for a gene, it is not evolving, and allele frequencies will stay the same across generations. They are: mutation, non-random mating, gene flow, finite population size genetic drift , and natural selection.

Why are recessive alleles slow to be eliminated from a population? It is almost impossible to totally eliminate recessive alleles from a population, because if the dominant phenotype is what is selected for, both AA and Aa individuals have that phenotype. Individuals with normal phenotypes but disease-causing recessive alleles are called carriers. What causes genetic drift? Genetic Drift. Random drift is caused by recurring small population sizes, severe reductions in population size called "bottlenecks" and founder events where a new population starts from a small number of individuals.

Genetic drift leads to fixation of alleles or genotypes in populations. Are dominant alleles more common? Dominant traits are not always the most common. Some people may think that dominant trait is the most likely to be found in the population, but the term "dominant" only refers to the fact that the allele is expressed over another allele. Contrary to what the first answerer said, even if the heterozygous individual displayed no ill effects, a deleterious effect in a 'homozygous recessive' individual is enough to eventually eliminate the recessive alleles from the population.

To put it another way, recessive alleles aren't automatically driven to extinction simply because they are recessive. Though it is definitely possible to eliminate recessive alleles from a population, there must be a specific reason for this to occur.

If you're interested, the population must break at least one of the five criteria of the Hardy-Weinberg equilibrium. In other words, it must be evolving. Posted by jeremy at Not all recessive alleles cause disease. Recessive alleles only show their effect if the individual has two copies of the allele also known as being homozygous? If you have two recessive copies of alleles for a trait then you will exhibit the recessive trait. For example: The gene for having blue eyes is recessive so in order to have blue eyes both the alleles should be recessive as they can only show their characteristics when it is homozygous when both alleles are same.

However, other scientists have reported that the interaction of two genes is responsible for this trait. This trait is reportedly due to a single gene; the presence of freckles is dominant, the absence of freckles is recessive1. The effect of the other allele, called recessive, is masked. A dominant allele is a variation of a gene that will produce a certain phenotype, even in the presence of other alleles.

A dominant allele typically encodes for a functioning protein. In codominance, different alleles are expressed in different areas, creating unique pattern. When a trait is dominant, only one allele is required for the trait to be observed. A dominant allele will mask a recessive allele, if present. A dominant allele is denoted by a capital letter A versus a. Since each parent provides one allele, the possible combinations are: AA, Aa, and aa. Begin typing your search term above and press enter to search.