- Sister chromatids
Sister chromatids are identical copies of a chromosome connected by a
centromere . Compare sister chromatids to homologous chromosomes, which are the two "different" copies of the same chromosome thatdiploid organisms (like humans) inherit, one from each parent. In other words, sister chromatids contain the same genes and samealleles , and homologous chromosomes contain the same genes but two copies of alleles, each of which might or might not be the same as each other.A full set of sister chromatids is created during the S subphase of
interphase , when all the DNA in a cell is replicated. Identical chromosome pairs are separated into two different cells duringmitosis , or cellular division.There is evidence that, in some species, sister chromatids are the preferred template for DNA repair [Kadyk and Hartwell, 1992; Genetics 132(2): 387–402] found within the cell during meiosis.
References
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