Search results
Results from the WOW.Com Content Network
A graphical representation of the typical human karyotype The human mitochondrial DNA. Human genetic variation is the genetic differences in and among populations.There may be multiple variants of any given gene in the human population (), a situation called polymorphism.
Genetic variation is the difference in DNA among individuals [1] or the differences between populations among the same species. [2] The multiple sources of genetic variation include mutation and genetic recombination. [3] Mutations are the ultimate sources of genetic variation, but other mechanisms, such as genetic drift, contribute to it, as ...
About 99.9% of the DNA-sequence in the human genome is conserved between individuals from all over the world, but some variation does exist. [1] Single nucleotide polymorphisms (SNPs) are considered to be the largest contributor to genetic variation in humans since they are so abundant and easily detectable. [2]
Some structural variants are associated with genetic diseases, however most are not. [3] [4] Approximately 13% of the human genome is defined as structurally variant in the normal population, and there are at least 240 genes that exist as homozygous deletion polymorphisms in human populations, suggesting these genes are dispensable in humans. [4]
Genetic markers have also been used to measure the genomic response to selection in livestock. Natural and artificial selection leads to a change in the genetic makeup of the cell. The presence of different alleles due to a distorted segregation at the genetic markers is indicative of the difference between selected and non-selected livestock. [5]
Genotype can also be used to refer to the alleles or variants an individual carries in a particular gene or genetic location. [2] The number of alleles an individual can have in a specific gene depends on the number of copies of each chromosome found in that species, also referred to as ploidy. In diploid species like humans, two full sets of ...
Fst values between European populations. The fixation index (F ST) is a measure of population differentiation due to genetic structure.It is frequently estimated from genetic polymorphism data, such as single-nucleotide polymorphisms (SNP) or microsatellites.
While there are significant differences among the genomes of human individuals (on the order of 0.1% due to single-nucleotide variants [9] and 0.6% when considering indels), [10] these are considerably smaller than the differences between humans and their closest living relatives, the bonobos and chimpanzees (~1.1% fixed single-nucleotide ...