Polygenic inheritance | definition of polygenic inheritance by Medical dictionary
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inheritance in which a measurable phenotype is generated by many loci, the contributions of which are statistically independent, additive, and of about equal value. (The latter are in accordance with the classic central limit therein and justify the use of the multivariate normal distribution in galtonian genetics.)
polygenic inheritance or quantitative inheritance a genetical system in which a number of genes (more than two) is involved in the control of a character, the character being described as ‘quantitative’ in that it shows a wide range of variability that can be measured (see HERITABILITY). Each ‘polygene’ in the system has only a small effect on the character and cannot be detected individually The expression of a polygenic character is strongly affected by the environment in which the individual exists. For example, human height is affected by diet, human intelligence scores are affected by the social background.
References in periodicals archive
Researchers also verified that resistance to the pathogen in this population has polygenic inheritance
, is conditioned by both additive and dominance genetic effects, and that genotypes with high resistance were rare in the germplasm at that time.
A number of cases are now recognised as familial, and within affected families the disorder exhibits either an autosomal recessive pattern of inheritance or a polygenic inheritance
pattern, ie involving several genes and the environment.
Vitiligo exhibits familial clustering in a non-Mendelian pattern that most likely reflects multifactorial, polygenic inheritance