The organism or gene that results from such a mutation(noun)
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Use "hypermutation" in a sentence
"The same thing goes for the immune system (progressive improvement of binding), but somatic hypermutation is an informationally-driven process, with selection (and, in the case of SMH, it is an artificial selection) accounting for only a small part of the innovation."
"When such patients were treated with Temodar and subsequently had a recurrence of the tumor, it was very likely to become resistant to treatment because of "hypermutation" -- an increased rate of gene changes that led to the tumor's ability to evade the drugs."
"It is thus not inconceivable that some of the sequences in the proposed Universal Genome in the Origin of Metazoa might have no immediate effect on fitness, but still have a function by acting as a reservoir of genetic material on which variation inducing mechanisms such as sequence duplication, somatic hypermutation, gene conversion and homologous recombination can act upon during periods of selection."