A mode of breeding involving two genetically- or consanguineously- related individuals or organisms
Inbreeding is a mode of breeding involving two individuals or organisms that are closely or genetically related. The mating of genetically-related parents would produce progenies with traits of higher predictability.
In humans, while inbreeding is acceptable in few certain cultures it is frowned upon largely by others and regarded as taboo. Medically, inbreeding in a consanguineous relationship is discouraged. It is because it increases the tendency of producing offspring with genetic anomalies and congenital birth defects. Inbreeding increases the chances of acquiring deleterious traits. And over time, there would be more individuals with recessive alleles or alleles in homozygous condition. An individual that acquires deleterious traits from inbreeding is referred to as an inbred. In other animals, inbreeding is a common mode of breeding. For instance, the common fruit fly females prefer to mate with their brothers than those who are not their brothers.1
A large gene pool is essential in increasing genetic diversity. The more diverse the alleles, the better are the chances of acquiring traits that boost biological fitness and survival. Inbreeding may decrease heterozygosity, and therefore, genetic diversity in the gene pool. A reduced biological fitness of a population caused by inbreeding is referred to as inbreeding depression.
- inbred (noun, adjective)
- inbreed (verb, to produce offspring through inbreeding)
1 “Incestuous Sisters: Mate Preference for Brothers over Unrelated Males in Drosophila melanogaster”. PLoS ONE. 7: e51293