Pleiotropy!
This is called polygenic inheritance. Multiple genes contribute to the expression of a single trait in polygenic inheritance, resulting in a continuum of phenotypic variation. Traits like height, skin color, and intelligence are influenced by multiple gene loci.
It was once believed that one gene controls one trait, so it is possible. Currently, the belief is that one gene can interact with other genes to control a trait, and that one gene can control more than one trait.
An example of a gene with three or more alleles for a single trait is the ABO blood group gene. This gene has three main alleles - A, B, and O - which determine blood type. The different combinations of these alleles result in the various blood types (A, B, AB, and O) observed in humans.
Natural selection acting on a single-gene trait can lead to changes in allele frequencies within a population. If individuals with a certain allele have a selective advantage, they are more likely to survive and reproduce, leading to an increase in the frequency of that allele in the population over time. This process is known as directional selection.
Height in humans is not an example of a single gene trait. It is a polygenic trait, meaning it is influenced by multiple genes as well as environmental factors. Multiple genes interact to determine an individual's height, making it a more complex trait.
This is called polygenic inheritance. Multiple genes contribute to the expression of a single trait in polygenic inheritance, resulting in a continuum of phenotypic variation. Traits like height, skin color, and intelligence are influenced by multiple gene loci.
It was once believed that one gene controls one trait, so it is possible. Currently, the belief is that one gene can interact with other genes to control a trait, and that one gene can control more than one trait.
phenotype
Polygenic traits result in more variation because so many more alleles are involved in the process of reproduction.
It was once believed that one gene controls one trait, so it is possible. Currently, the belief is that one gene can interact with other genes to control a trait, and that one gene can control more than one trait.
An example of a gene with three or more alleles for a single trait is the ABO blood group gene. This gene has three main alleles - A, B, and O - which determine blood type. The different combinations of these alleles result in the various blood types (A, B, AB, and O) observed in humans.
A polyallelic trait is a trait controlled by multiple alleles (variants of a gene) at a single gene locus. This means there are more than two possible alleles that can influence the trait's expression, resulting in a range of phenotypic variations. This can lead to a complex inheritance pattern.
Polygenic inheritance occurs when a trait is controlled by two or more genes. Each gene contributes a small amount to the phenotype of the trait, resulting in a continuous range of phenotypic variations.
Inheritance in which more than one gene pair affects the appearance of a particular trait. Polygenetic inheritance refers to the non-Mendelian form of inheritance in which a particular trait is produced by the interaction of many genes.
When two or more forms of a gene for a single trait exist, some forms may be dominant and others recessive. Dominant forms of a gene will be expressed over recessive forms in the phenotype. This is known as codominance or incomplete dominance.
Natural selection acting on a single-gene trait can lead to changes in allele frequencies within a population. If individuals with a certain allele have a selective advantage, they are more likely to survive and reproduce, leading to an increase in the frequency of that allele in the population over time. This process is known as directional selection.
A gene can have multiple forms, which are called Alleles. While a single gene may code for a trait in an organism, when multiple alleles exist for that gene, each different may produce a different character of that trait. For example, a person has two copies of the gene that codes for ABO blood type. There are three different alleles for this gene, A, B and O. This results in six different combinations of the alleles that the person can have (the genotype), which in turn results in four expressions of the gene in the person (called the phenotype), which is the blood type of the person.