... after one generation of random mating , the genotype
frequencies at a single gene locus will become ... drift . Assortative mating will only change the genotype
frequencies of those genes that are desired. ... )
aa ( q 2 )
So the final three possible genotype
frequencies, in the offspring, if the alleles are ...
... on the two corresponding chromosomes (e.g. the genotype
is AA or aa ).
A homozygous dominant genotype
occurs when a particular locus comprises two ... trait (e.g. AA ).
A homozygous recessive genotype
occurs when a particular locus comprises two ...
... This genetic similarity can be beneficial if the genotype
is well suited to a stable environment, but ... if a new predator or pathogen appears and a genotype
is particularly defenseless against it, an ... the genetic recombination that produces a novel genotype
in each individual. Similar arguments apply to ...
... Phenotype is determined to some extent by genotype
, or by the identity of the alleles that an ... of molecular biology .
The interaction between genotype
and phenotype has often been described using a simple equation:
Phenotype = genotype
A phenotype is any detectable ...
... map the resulting population ( P 2 ) back to genotype
space ( G 2 ) where Mendelian genetics can ... biology, or development , that transform a genotype
into phenotype. We will refer to this as the " ... traditional population genetics operating in the genotype
space and the biometric theory used in plant ...
... of alleles -- in other words, to evolution . Besides selection, these forces include genetic drift , mutation and migration .
If there are ten individuals in a population and at a given locus there are two possible alleles, A and a , then if the ...
Some biologists at one time believed that genetics, which seemed to postulate a one-to-one correspondence between genotype
and phenotype , could not explain cell differentiation. They developed a theory that each undifferentiated cell underwent a crisis that determined ...
... adaptive landscapes are used to visualize the relationship between genotypes (or phenotypes ) and replicatory success. It is assumed that every genotype
has a well defined replication rate (often referred to as fitness ). The set of all possible genotypes and their related fitness values is then ...
... dominant and recessive traits, the distinction between a heterozygote and homozygote, and the difference between what would later be described as genotype
and phenotype. Mendel's concept was finally named when Wilhelm Johannsen coined the word gene in 1909 .
In the early 1900s , Mendel's work ...
... are examined in searches for chromosomal aberrations , and may be used to determine other macroscopically visible aspects of an individual's genotype
, such as sex (XX vs. XY pair). The study of karyotypes is known as karyology .
Normal human karyotypes are denoted 46,XX (for most women ) ...
... for the neutral case, and is not necessarily true for the case when some alleles are more or less fit than others, for example when the fittest genotype
is a heterozygote (a situation often referred to as overdominance or heterosis ).
In the case of overdominance, because Mendel's second law ...
... who test as type O may have the Bombay phenotype : they have inherited two recessive alleles of the H gene, (their blood group is O h and their genotype
is "hh"), and so do not produce the "H" protein that is the precursor to the "A" and "B" antigens. It then no longer matters whether the A or B ...