Population Genetics - 2021 Words

In 1831, Charles Darwin, proposed a theory of evolution occurring by the process of natural selection. This has come to be known as the Theory of Natural Selection. Darwin worked on his theory for 20 years and after learning that Alfred Russel Wallace, another naturalist, had developed similar ideas, the two made a joint announcement of their discovery in 1858. Darwin published On the Origin of Species by Means of Natural Selection in 1859, 28 years after he proposed his theory of natural selection. [1] Darwin’s theory of natural selection states that evolutionary change comes through the production of variation in each generation and differential survival of individuals with different combinations of these variable characters. [2]†¦show more content†¦[4] A definitive description of Huntington’s Chorea occurred, when George Huntington submitted his article On chorea to the Medical and Surgical Reporter of Philadelphia, USA, in 1872, 31 years after Waters gave his description of the disorder. Waters described a disorder which is markedly hereditary, very rarely makes its appearance before adult life, in all cases induces a state of more or less perfect dementia and never ceases while life lasts. The disease was recorded early on by observers; however Waters’ description was the first detailed description of the disease. It is believed that the disease was present among the population at a much earlier date as it is caused by a dominant allele. Because of its long history, and the fact that the mutation rate for Huntingtons chorea is among the lowest recorded for any inherited condition, the disease has great potential in genealogical investigations. The Afrikaner population posed as a great source to study the disease be cause of the excellent recording of the origins and history of the Afrikaner nation. The excellent documentation facilitated efforts to trace the disease back to the earliest transmission of the gene to South Africa. In their research they found that the only previous attempt to investigate the genealogy of this disease inShow MoreRelatedGenetic Changes Within The Populations : The Consequences Of Selection1115 Words   |  5 PagesLab Report 1 Genetic Changes in Populations: The Consequences of Selection General Biology II Lab Junyao Li Introduction In this lab, we explore the reason genetic changes happened within a population. We use bean-bag model to simulate allele and genotype frequencies for three generations of deer mice under three different selective regimes. Then, we use the Hardy-Weinberg Principle to assess the selection and evolution experienced by deer mice. The Hardy-Weinberg Principle is one of the mostRead MorePopulation Genetics Of Chickpea And Its Wild Progenitors C1755 Words   |  8 PagesPopulation genetics of chickpea and its wild progenitors C. reticulatum and C. echinospermum Susan Moenga Introduction Chickpea, Cicer arietinum, is the second most widely grown legume in the world, cultivated on ~11.5 million ha mostly in India and Ethiopia (FAOSTAT, 2013). Genetic and molecular evidence have demonstrated that C. reticulatum is the progenitor of the cultivated pulse, with Nguyen et al., (2004) and Sethy et al., (2006) both supporting C. reticulatum and C. echinospermum (both restrictedRead MoreGenetic Variation Between Human Populations3106 Words   |  13 PagesPopulation demographic factors such as age, sex, diet and ethnicity explain the largest proportion of genetic variation between human populations (Fumagalli et al., 2011). Infectious agents including viruses, bacteria and protozoa are likely one of the strongest evolutionary drivers of the remaining genetic diversity within and between populations, as a result of the selective pressure they inflict in regions where infection is endemic. Mortality is the strongest selective pressure which is imposedRead MorePopulation Genetic History Of The Indian Peninsula Endowed With Heterogenous Complexity Essay1569 Words   |  7 PagesPopulation genetic history of the Indian peninsula en dowed with heterogenous complexity has received a huge attention worldwide. The incessant waves of migration of people from ancient to present time and from various directions across the world have significantly contributed in India being a genetic melting pot. The earliest inhabitant being the Austro- Asatic people around 60,000 years ago from Africa, entered India through western corridor(Nei and Ota 1991; Majumder 2001) or they have migratedRead MoreGenetic Structure and Differentiation of Four Populations of Afghan Pika (Ochotonarufescens) based on mitochondrial cytochrome b gene in Iran541 Words   |  3 PagesWe determined mtDNA sequence variation in four populations of Afghan Pika from Northern Khorasan Province, North-eastern Iran, focusing on differentiation and genetic diversity. The result of cytochrome b region of mitochondrial gene variation indicated high levels of haplotype diversity (0.834 ±0.059) among all individuals of O.rufescens and low nucleotide diversity ( 0.0024 ±0.0008). In comparison with other Pikas, afghan pika showed low haplotype diversity but nucleotide diversity was high in AfghanRead MoreDiscuss the Issues Related to Genetic Diversity: Mutations, Sexual Reproduction, Migration, and Population Size.1087 Words   |  5 PagesDiscuss the issues related to genetic diversity: mutations, sexual reproduction, migration, and population size. --- Generally speaking, there are numerous issues related to genetic diversity which include mutations, sexual reproduction, migration, and population size. To begin with, mutations (any change in the DNA sequence of an organism) introduce new genetic information into a population by altering alleles (a form of a gene usually arising through mutation) that are already present. OccasionallyRead MorePopulation Genetics2030 Words   |  9 Pagesalleles in the gene pool of a population. Hardy and Weinberg, and the population geneticists who followed observed that evolution will not occur in a population if seven conditions are met: 1. Mutation is not occurring 2. Natural selection is not occurring 3. The population is infinitely large 4. All members of the population breed 5. All mating is totally random 6. Everyone produces the same number of offspring 7. There is no migration in or out of the population With their observations theyRead MorePopulation Genetics Of Single Loci Essay1765 Words   |  8 PagesPopulation genomic studies have the ability to acknowledge several unanswered questions about microbial pathogens by helping the connection of genes indispensable ecologically significant traits such as malevolence aspects and its modification to humans and other host species. To recognize environmental, historical, transformational process that form naturally transforming genetic alteration is the main purpose of population genetics. The ability to identify and define these processes from naturalRead MoreOn The Origin of Species by Charles Darwin915 Words   |  4 Pages(MRO) model (3). The RAO model finds its origin in Darwins The Descent of Man, published in 1871, where he hypothesizes that humans descent from a single species that resided in Africa (4). Today, the RAO model suggests that all non-African populations have a common Homo sapiens ancestor from the African regions that evolved around 120 to 200 thousand years ago and supplanted archaic hominids around the world (3,5). This model is supported by paleontological evidence, as the earliest anatomicallyRead MoreThe Five Forces of Evolution643 Words   |  3 PagesThere are five major forces behind evolution. One of these is genetic drift which is a sudden or drastic change in the gene pool of a small population due to a sudden event that wipes out part of the population. An example of this could be a population of butterflies that varies from light to dark that live in a garden. If the garden was suddenly re-planted with just white flowers, the populations gene pool would skew towards the light side. This would happen because the dark butterflies would