by Open Science Repository Biology
(December 3, 2012)
Abstract: In the past century two versions of the principle of segregation have been used in biology, and both can claim to have connections to concepts presented by Mendel. The cytological version applies to all types of cell division and, by achieving transmission of full chromosome sets, acts to conserve the genome. Here independent assortment, not segregation, produces new genetic combinations. Some important features of the cytological version of segregation are consistent with Mendel’s law of combination, and with some of his other statements. In contrast, the classical version limits segregation to the separation of differing alleles during meiosis, and segregation and independent assortment can both result in new genetic combinations. A survey of articles from the journal Science indicates that recently the cytological version of segregation has increased in use. It is concluded that this cytological/cell biological version of segregation is broader and conceptually more powerful compared to the classical version. This cell biologists’ version of segregation should be considered for wider adoption as a useful expansion of the biological principle of segregation.
Keywords: assortment, Bateson, cytology, Mendel, Mendelian principles, Morgan, segregation.