... that gene. An organism which has two different alleles
of the gene is said to be heterozygous . Often ... (sometimes called blending inheritance ) when alleles
blend their traits in the phenotype . An ... flowers with codominant "blue" and "purple" alleles
for petal color, the resulting offspring would ...
... an allele that has a frequency of 20%. However, alleles
distribute randomly only in the absence of ... equilibrium .
The frequencies of all the alleles
of a given gene often are graphed together as an ... to changes in the distribution and frequencies of alleles
-- in other words, to evolution . Besides ...
... specifically as a change in the frequency of alleles
in a population from one generation to the ... of traits
While mutation can create new alleles
, other factors influence the frequency of ... between successive generations may result in some alleles
disappearing from the population. Two separate ...
... Variants of a single gene are known as alleles
, and differences in alleles
may give rise to differences in traits, for ... allele is called the wild type allele, and rare alleles
are called mutants .
Normally, RNA is an ...
... acts on populations , altering the frequency of alleles
and the predominance of traits amongst members ... fluctuations (sampling error ).
When the alleles
of a gene do not differ with regard to fitness, ... small, genetic drift will be stronger.
usually have a finite lifetime. As the frequency ...
... refers to the molecular process by which alleles
at two genes in a linkage group can become separated. In this process alleles
are replaced by different alleles
from the same genes thereby preserving the ...
... In the simplest case of a single locus with two alleles
A and a with allele frequencies of p and q ...
5.1 Generalization for more than two alleles
5.2 Generalization for polyploidy
5.3 ... statistical description for the HWP, is that the alleles
for the next generation for any given individual ...
... are diploid or polyploid and have the same alleles
at a locus (position) on homologous ... occurs when a particular locus comprises two alleles
for the dominant trait (e.g. AA ).
A ... occurs when a particular locus comprises two alleles
for the recessive trait (e.g. aa ).
Major histocompatibility complex
... HLA-DRB1, have roughly 250, 500, and 300 known alleles
respectively -- diversity which is truly ... classical loci routinely find tens to a hundred alleles
-- still highly diverse. And perhaps even more remarkable is that many of these alleles
are quite ancient: it is often the case that an ...
... in inherited characters. This is the concept of alleles
are different versions of genes that impart the ... comes from the mother, one from the father. These alleles
may be the same (true-breeding organisms, e.g. ...
2.4 The neutral theory
2.5 Infinite alleles
2.6 Infinite sites model
3 ... to the next generation. In this way, the alleles
that these surviving individuals contribute to ... developing workaround solutions.
The Japanese geneticist Motoo Kimura ...
Neutral theory of molecular evolution
... the result of genetic drift acting on neutral alleles
. A new allele arises typically through the ... new neutral alleles.
Through drift, these new alleles
may become more common within the population. ... revolved around the relative percentages of alleles
that are "neutral" versus "non-neutral" in any ...
... type is controlled by a single gene with three alleles
: i , A , and B . The gene encodes a ... phenotype : they have inherited two recessive alleles
of the H gene, (their blood group is O h and ... for the A allele. However, if only recessive alleles
for the H antigen are inherited (hh), as in the ...
... variations of that sequence are called alleles. alleles
can be significantly different and produce different product RNAs .
Combinations of different alleles
thus go on to generate different traits ... flow charted above. For example, if the alleles
on homologous chromosomes exhibit a "simple ...
Ewens's sampling formula
... at a particular locus then the probability that there are a 1 alleles
represented once in the sample, and a 2 alleles
represented twice, and so on, is
for some positive number ...
... gene pool of a species or a population is the complete set of unique alleles
that would be found by inspecting the genetic material of every living ... reduced fitness and an increased chance of extinction .
When many alleles
exist for a given gene or locus , a population is said to be polymorphic ...
... over time. Although, strictly speaking, allozymes represent different alleles
of the same gene , and isozymes represent different genes whose ... as isozymes ) and (2) enzymes that are the product of different alleles
of the same gene (described as allozymes ).
Isozymes are usually the ...
... sequence) on a chromosome . A locus can be occupied by any of the alleles
of the gene. Diploid or polyploid cells are either homozygous (have the same allele at a locus) or heterozygous (have different alleles
at a locus).
In mathematics , a locus is the set of points ...
... is determined to some extent by genotype , or by the identity of the alleles
that an individual carries at one or more positions on the chromosomes . ... by environmental factors. Thus, the identity of one or a few known alleles
does not always enable prediction of the phenotype.
... development, this results in different regions of the adult body having different chromosomes inactivated. This can be significant if different alleles
of a gene are present on the different chromosomes; in some regions of the body one allele will be active, and in other regions the other will. This ...
... Heterozygote cells are diploid or polyploid and have different alleles
at a locus (position) on homologous chromosomes . When an organism is referred to as a heterozygote, or being heterozygous for a specific ...
... (through crossing over ) of genes, ensuring heritable variation. The reduction of chromosomes from the diploid to the haploid condition separates alleles
so that each gamete carries a sole allele for a gene locus. In addition, the orientation of the metaphase I/II equatorial lining-up is random, ...
Modern evolutionary synthesis
... ) and recombination (crossing over of homologous chromosomes during meiosis ). Evolution consists primarily of changes in the frequencies of alleles
between one generation and another as a result of genetic drift , gene flow and natural selection . Speciation occurs gradually when ...
... (computer game) .
Natural selection is the primary mechanism within the scientific theory of evolution , i.e. it alters the frequency of alleles
within a population . After a century of obscure and vague preliminary formulations, it was proposed as the main mechanism of evolution by ...
Polymerase chain reaction
... is homozygous T, homozygous C, or heterzygous T/C. This methodology has several applications, such as amplifying certain haplotypes (when certain alleles
at 2 or more SNPs occur together on the same chromosome [Linkage Disequilibrium]) or detection of recombinant chromosomes and the study of meiotic ...