How does inbreeding and outbreeding affect the offspring?
Inbreeding and outbreeding are two breeding techniques performed by plant and animal breeders. Inbreeding is done between close relatives to maintain beneficial traits over generations. Inbreeding increases the homozygosity in the offspring. It negatively affects the offspring by giving more chance to express deleterious recessive mutations.
What are the general effects of inbreeding depression?
Inbreeding depression is thought to be caused primarily by the collection of a multitude of deleterious mutations, few in themselves fatal, but all diminishing fitness. Normally, in an outbreeding population these alleles would be selected against, hidden, or corrected by the presence of good alleles (versions of genes) in the population.
Why do most living things avoid inbreeding?
Humans have very strong taboos against mating with relatives. Even fruit-flies apparently have a sensing mechanism to avoid too close of inbreeding, even in a closed population they maintain more genetic diversity than they ought to by random mating. Why do living things avoid inbreeding?
What kind of disorders can be caused by inbreeding?
Disorders From Inbreeding. The risk of a child developing an autosomal recessive disorder increases with inbreeding. Carriers of a recessive disorder may be unaware they possess a mutated gene because two copies of a recessive allele are needed for gene expression.
What is the difference between outbreeding and inbreeding depression?
In biology, outbreeding depression is when crosses between two genetically distant groups or populations results in a reduction of fitness. The concept is in contrast to inbreeding depression, although the two effects can occur simultaneously. Outbreeding depression is a risk that sometimes limits the potential for genetic rescue or augmentations.
How does inbreeding affect the health of the population?
Inbreeding may result in a greater than expected phenotypic expression of deleterious recessive alleles within a population. As a result, first-generation inbred individuals are more likely to show physical and health defects, including: Reduced fertility both in litter size and sperm viability
How does outbreeding lead to loss of fitness?
Outcrossing between individuals with differently adapted gene complexes can result in disruption of this selective advantage, resulting in a loss of fitness. The different mechanisms of outbreeding depression can operate at the same time. However, determining which mechanism is likely to occur in a particular population can be very difficult.
What are the three main mechanisms of outbreeding?
There are three main mechanisms for generating outbreeding depression: Fixed chromosomal differences resulting in the partial or complete sterility of F 1 hybrids. Adaptive differentiation among populations Population bottlenecks and genetic drift
