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Inheritance is the passage of hereditary traits passed down from one generation to another. These traits have been acquired from your parents and will be transferred to your children. This division of biology is called genetics[1]. In genetic speaking, inheritance is DNA involved event, which passes on the traits to the next generation, including characteristics, diseases as well as personality

Inheritance is sub-categorised into Dominant/Recessive, Co-dominance, Incomplete Dominance and Polygenic Inheritance based on the transfer and expression of certain alleles over several generations from the parent to the progeny. Various factors such as environmental conditions, diet and health induce certain changes in the organisms so that variation is carried out and organisms can evolve so as to counteract the harsh changes they succumb to in their habitat.

Dominant/Recessive: They are inheritance patterns that determine several phenotypic traits in organisms helping us predict the outcome of genetic disorders and key physical characteristics of progeny over several generations[2]. Eg: Height in pea plants, Colour Blindness in humans.

Co-dominance: Two different alleles equally expressed in an organism hence expressing unique characteristics.Therefore offsprings alleles are neither recessive nor dominant. Eg: Blood groups in humans, Co-dominance in Roan cattle.

Incomplete Dominance: Incomplete Dominance is a form of intermediate inheritance thus displaying a blend of alleles resulting in a third phenotype. Eg: Incomplete Dominance is snapdragon

Polygenic Inheritance: Polygenic Inheritance is when multiple alleles are used to determine certain functions or phenotypes in an organism[3]. Eg: Height in humans, Coat colour in Labradors.


  1. Tortora G., Anagnostakos N. (1990) Principles of Anatomy and Physiology. New York: Harper and Row
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