Search results
Results from the WOW.Com Content Network
A polygene is a member of a group of non-epistatic genes that interact additively to influence a phenotypic trait, thus contributing to multiple-gene inheritance (polygenic inheritance, multigenic inheritance, quantitative inheritance [1]), a type of non-Mendelian inheritance, as opposed to single-gene inheritance, which is the core notion of Mendelian inheritance.
When Mendel's work on inheritance was rediscovered in 1900, scientists debated whether Mendel's laws could account for the continuous variation observed for many traits. [citation needed] One group known as the biometricians argued that continuous traits such as height were largely heritable, but could not be explained by the inheritance of single Mendelian genetic factors.
A trait can also be determined by multiple genes, known as polygenic inheritance. Genes also have different levels of penetrance, which determines how much they will be expressed. In addition, the environment affects the expression of numerous genes, therefore making the test cross inapplicable in many cases.
The infinitesimal model, also known as the polygenic model, is a widely used statistical model in quantitative genetics and in genome-wide association studies.Originally developed in 1918 by Ronald Fisher, it is based on the idea that variation in a quantitative trait is influenced by an infinitely large number of genes, each of which makes an infinitely small (infinitesimal) contribution to ...
On a pedigree, polygenic diseases do tend to "run in families", but the inheritance does not fit simple patterns as with Mendelian diseases. This does not mean that the genes cannot eventually be located and studied. There is also a strong environmental component to many of them (e.g., blood pressure). Other such cases include: asthma
An example of the codominant inheritance of some of the four blood groups. Mendelian traits in humans are human traits that are substantially influenced by Mendelian inheritance. Most – if not all – Mendelian traits are also influenced by other genes, the environment, immune responses, and chance.
In fact, the terms 'multifactorial' and 'polygenic' are used as synonyms and these terms are commonly used to describe the architecture of disease causing genetic component. [2] Multifactorial diseases are often found gathered in families yet, they do not show any distinct pattern of inheritance.
Human genetics is the study of inheritance as it occurs in human beings.Human genetics encompasses a variety of overlapping fields including: classical genetics, cytogenetics, molecular genetics, biochemical genetics, genomics, population genetics, developmental genetics, clinical genetics, and genetic counseling.