The spontaneous azaguanine-resistant mutants of diploid human fibroblasts

Comparative lesion sequencing provides insights into tumor evolution

“…14, the point mutation rate in colorectal cancers is estimated to be 4.6 ϫ 10 Ϫ10 mutations per base pair per generation. This rate is slightly less than that measured in various normal cell types [Ϸ10 ϫ 10 Ϫ10 mutations per base pair per generation (22)(23)(24)(25)]. Additional details about this estimate are provided in supporting information (SI) Methods.…”

Molecular and cellular aspects of HTLV-1 associated leukemogenesis in vivo

“…1 The overall mutation rate of somatic human cells has been estimated at 1.4 × 10 −10 nucleotides/cell/division or 2.0 × 10 −7 mutations/gene/cell division. 97 The mean mutation frequency of 10 6 per HTLV-1 infected lymphocytes 18 might account for the oncogenic potential of the virus. Yet, a conundrum remains: given the mutational pressure of elevated levels of somatic mutations, why is the lifetime risk of ATLL as low as 3-5%?…”

Mutation studies with human fibroblasts.

“…The average incidence of AG-resistant (AGr) clones is about 5 x 10-6 (2). A simple principle is applied in detecting the mutants.…”

“…One was performed with cells from the human prototype of Type II mutants, which I mentioned above. In this case, we know that the HG-PRT is qualitatively altered as the result of a mutation in an X-chromosomal gene (2). Therefore, the properties of hybrids obtained with this mutant will provide a standard for evaluating the results obtained with in vitro mutants.…”