Replication Error Definition
Replication Error – a mistake that occurs when dna sequences duplicate before cell division. Replication errors are accountable for chromosomal disorders such as autosomal trisomy, in which a gamete (also called a sex cell or germ cell) receives two copies of a chromosome instead of the normal single copy.
Gametes, which are haploid cells, each carry one-half the complement of chromosomes so when they unite to form the zygote that will become a new human being, the zygote contains the full complement of genetic material.
With a replication error such as an autosomal trisomy, the zygote receives an extra chromosome two copies from one gamete and one copy from the other gamete. The result is a chromosomal disorder such as Down syndrome.
Replication errors also may have harmless consequences when they occur in DNA sequences that do not encode structural or regulatory sequences of gene activity.
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