Some common examples of polygenic traits in humans are height, hair color, and eye color. In animals, behavioral characteristics are controlled by multiple genes. Polygenic characters are expressed in continuous variation. People with same genotype may have different phenotype.
Likewise, what does a polygenic trait mean?
A polygenic trait is one whose phenotype is influenced by more than one gene. Traits that display a continuous distribution, such as height or skin color, are polygenic.
Subsequently, question is, how do you know if a trait is polygenic? If you are dominant for all of the alleles for height, then you will be very tall. There is also a wide range of skin color across people. Skin color is also a polygenic trait, as are hair and eye color. Polygenic inheritance often results in a bell shaped curve when you analyze the population (Figure below).
Similarly, you may ask, which trait is polygenic in humans?
Polygenic inheritance occurs when one characteristic is controlled by two or more genes. Often the genes are large in quantity but small in effect. Examples of human polygenic inheritance are height, skin color, eye color and weight. Polygenes exist in other organisms, as well.
What is a polygenic trait example?
These genes, called polygenes, produce specific traits when they are expressed together. Examples of polygenic inheritance in humans include traits such as skin color, eye color, hair color, body shape, height, and weight.
19 Related Question Answers Found
Is skin color a discrete trait?
An in-depth discussion of discrete and continuous traits requires some background about the organization of genetic material. Genes are short sections of DNA that are associated with specific genetic traits. For example, in humans, genes help determine characteristics such as skin and hair color.
Is blood type A polygenic trait?
An example of a human multiple allele trait is ABO blood type, for which there are three common alleles: IA, IB, and i. Codominance occurs when two alleles for a gene are expressed equally in the phenotype of heterozygotes. Examples of human polygenic traits include skin color and adult height.
What are examples of polygenic inheritance?
Examples of polygenic inheritance in nature can be found in many places: in human height, skin color, and hair color; in animal size, longevity, or disease resistance; and in plants with grain color, length of maize, or flower size. All of these traits are influenced by multiple genes and considered polygenic.
What is a monogenic trait?
A monogenic trait is a characteristic that is produced by a single gene or a single allele. A gene is a DNA segment that is responsible for physical traits and the phenotype of an organism. An allele is one of a pair of genes on a chromosome – the pair controls the same trait.
Is eye color polygenic?
In humans, the inheritance pattern followed by blue eyes is considered similar to that of a recessive trait (in general, eye color inheritance is considered a polygenic trait, meaning that it is controlled by the interactions of several genes, not just one).
Is red hair polygenic?
Red hair is not polygenic, but it does use incomplete dominance. That means there is only one gene pair responsible for red hair, and it can add up to 0, 1, or 2. You will be perceived as having light red hair and considered a redhead. Or you may result in strawberry blond which some people consider red, others do not.
Why are polygenic traits important?
This type of polygenic phenotypic trait is quantitative because it has a continuous variation over a range of measurement. It is also multifactorial because there are multiple factors that play a role in a trait. In the case of polygenic inheritance, these factors are multiple genes.
Is epistasis polygenic inheritance?
Polygenic inheritance: one character is controlled by more than one gene & inheritance of that character is called polygenic inheritance. Such gene called epistatic gene. The potential of a gene (a1) which suppresses the expression of another gene (b1&b2) that in different loci is called epistasis.
What does epistatic mean?
Epistasis is the phenomenon wherein the effect of one gene (locus) is dependent on the presence of one or more ‘modifier genes’, i.e. the genetic background.
How is height inherited?
Height is not solely determined by genetics. Nutrition, connection to quality food and socioeconomic class all influence overall height. Yet, for some, inherited genetic changes result in shorter height. Achondroplasia is one of many forms of dwarfism, occurring due to an inherited change in a person’s genetics.
How can one gene affects many traits?
A pleiotropic gene is a single gene that controls more than one trait. The term pleiotropy is derived from the Greek words pleio, which means “many,” and tropic, which means “affecting.” Genes that affect multiple, apparently unrelated, phenotypes are thus called pleiotropic genes (Figure 1).
How do polygenic traits work?
Polygenic Traits Definition. Polygenic traits are traits that are controlled by multiple genes instead of just one. The genes that control them may be located near each other or even on separate chromosomes. Because multiple genes are involved, polygenic traits do not follow Mendel’s pattern of inheritance.
What does polygenic mean in psychology?
Polygenic. Polygenic refers to DNA traits such as skin color, hair color, eye color, and stature that are influenced by multiple genes rather than other traits that exist as a yes or no (such as gender or blood type).
What is polygenic disease?
Polygenic disease: A genetic disorder that is caused by the combined action of more than one gene. Because such disorders depend on the simultaneous presence of several genes, they are not inherited as simply as are single-gene diseases.
Is skin color a single gene trait?
Single genes code for most traits Multiple genes, not just a single gene, determine most traits in humans such as height, eye color, and skin color. When a trait is controlled by more than one gene it is called polygenic.
How is human skin color an example of polygenic inheritance?
Polygenic Inheritance: Human skin color is a good example of polygenic (multiple gene) inheritance. A genotype with all “dominant” capital genes (AABBCC) has the maximum amount of melanin and very dark skin. A genotype with all “recessive” small case genes (aabbcc) has the lowest amount of melanin and very light skin.
What is a simple Mendelian trait?
Mendelian Traits are those traits which follow Mendel’s rules of only 2 possible versions of a gene (1 dominant, 1 recessive). There are only a few examples of this in humans. 1. Use the chart below to determine your phenotype (observable characteristic) and possible genotype(s) (a pair or pairs of alleles).
Is eye color a Mendelian trait?
It was originally thought that eye color was a simple Mendelian trait, meaning it was determined by a single gene, with brown being dominant and blue recessive. It is now clear that eye color is a polygenic trait, meaning it is determined by multiple genes.
What is an example of epistasis?
An example of epistasis is pigmentation in mice. The wild-type coat color, agouti (AA), is dominant to solid-colored fur (aa). The recessive c allele does not produce pigment, and a mouse with the homozygous recessive cc enotype is albino regardless of the allele present at the A locus.