Question 29
While examining the mitotic stage in a tissue, one finds some cells with 16 chromosomes and some with 32 chromosomes. What possible reasons could you assign to this difference in chromosome number. Do you think cells with 16 chromosomes could have arisen from cells with 32 chromosomes or vice-versa?
Such a condition may arise in case of a mosaic or mosaicism, which denotes preserve of two or more populations of cells with different genotypes in one individual.
It can result from various mechanisms including non-disjunction, anaphase lagging and endoreplication. It may also result from a mutation during development which is propagated to only a subset of the adult cells.
In this case, cells with 16 chromosomes could have arisen from cells with 32 chromosomes.