
Figure 1. Pedigree showing examples of genetic death.
Genetic death is defined as the removal of a gene from the gene pool of a population. It can be the result of infertility, failure to reproduce, or death before sexual maturity of all indviduals carrying that gene. Genetic death is not necessarily associated with poor health or loss of life, but rather refers to the impediment of genes being passed on to future generations.
Genetic Death and Evolution[]
Genetic death can play a role in evolution by facilitating natural selection. Loss of harmful genes can be beneficial to future generations that are born from that gene pool, potentially increasing fitness. Examples of genetic death constituting a catalyst for evolution include genes can be seen in pathogen resistance, such as the genetic loss of certain cellular receptors that inhibit entry of pathogens into target cells exhibited in genotypes with malaria or AIDS resistance.
LESS IS MORE: Olson (1999) describes the concept of gene loss as an engine of evolutionary change. Through natural seleciton, deliterious mutuations of certain genes can be eliminated from the gene pool which can lead to increased fitness. Examples the concept of less is more regarding the propagation of gene loss, include resistance to malaria and AIDs which are both associated with null mutations of specific genes.
Humans are said to each have 100 "broken genes": http://www.livescience.com/18518-humans-broken-genes.html
Olson, M. V. (1999). When less is more: gene loss as an engine of evolutionary change. American journal of human genetics, 64(1), 18. 5 days ago by Jenkainz
References[]
Medical Dictionary. (n.d.). Medical Dictionary. Retrieved November 4, 2013, from http://medical-dictionary.thefreedictionary.com/[]
Mosby, I. (2009). Mosby's medical dictionary (8th ed.). St. Louis, MO: Mosby.
Olson, M. (1999). When Less Is More: Gene Loss As An Engine Of Evolutionary Change. The American Journal of Human Genetics, 64(1), 18-23.