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.
What human traits are polygenic?
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
.
What is a trait determined by multiple alleles?
Traits controlled by a single gene with more than two alleles are called multiple allele traits. An example is
ABO blood type
. Your blood type refers to which of certain proteins called antigens are found on your red blood cells.
What is a polygenic inheritance pattern?
Polygenic inheritance (biology definition):
A non-Mendelian pattern of inheritance in which a particular trait is produced by the interaction of genes at many loci
(i.e. polygenes). Etymology: “poly”, meaning “many”.
What are 3 examples of polygenic traits?
Some examples of polygenic inheritance are:
human skin and eye color; height, weight and inteligence in people
; and kernel color of wheat.
What is an example of multiple alleles?
An excellent example of multiple allele inheritance is
human blood type
. Blood type exists as four possible phenotypes: A, B, AB, & O. There are 3 alleles for the gene that determines blood type.
What is multiple Allelism give an example?
The major example of multiple allelism is
ABO blood grouping in humans
. Complete answer: Multiple alleles refer to the occurrence of three or more than three alleles for a particular gene. … But, in the case of multiple allelism, more than two forms of the gene can be present for the same locus.
What is not a polygenic trait?
Blood type AB
in humans, for instance, is not a polygenic trait. Rather, it is a case of codominance. The two alleles for A and B antigens on the red blood cells of blood type AB individuals are dominant, and therefore are expressed together.
Is height a dominant trait in humans?
Yes and
No
. Humans come in a variety of heights — and genetics play a key role in determining whether you will be short or tall. There’s much more than just heredity to consider before assuming a person will automatically be the same height as their parents.
What is a pleiotropic trait?
A pleiotropic gene is
a single gene that controls more than one trait
. © 2008 Nature Education All rights reserved. During his study of inheritance in pea plants, Gregor Mendel made several interesting observations regarding the color of various plant components.
What is an example of Mendelian inheritance?
Examples include
sickle-cell anemia, Tay–Sachs disease, cystic fibrosis and xeroderma pigmentosa
. A disease controlled by a single gene contrasts with a multi-factorial disease, like heart disease, which is affected by several loci (and the environment) as well as those diseases inherited in a non-Mendelian fashion.
How is height passed down genetically?
The main factor that influences a person’s height is their genetic makeup. However, many other factors can influence height during development, including nutrition, hormones, activity levels, and medical conditions. Scientists believe that genetic makeup, or DNA, is responsible for
about 80% of a person’s height
.
What does monogenic inheritance mean?
Monogenic inheritance refers to
the inheritance that is controlled by the alleles for one particular locus
, as opposed to di- tri- or polygenic control exerted by two three or many non-allelic genes. Mendelian Forms of Human Hypertension and Mechanisms of Disease.
How do you identify a polygenic trait?
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.
Is intelligence a polygenic trait?
Intelligence Is a
Polygenic Trait
These findings show that intelligence is a highly polygenic trait where many different genes would exert extremely small, if any, influence, most probably at different stages of development.
Why is it harder to determine which phenotype a person will have when a trait is controlled by many genes?
When there are large numbers of genes involved,
it becomes hard to distinguish the effect of each individual gene
, and even harder to see that gene variants (alleles) are inherited according to Mendelian rules.
