There is no selection in the detection of the mutant population that arises as the result of DNA damage and mutant colonies unable to grow in minimal medium are clonal.
In HIV, the genetic events are mutations in the genome of the dominant strain in the infecting virus population that arise when a patient receives a specific medication.
Their model goes beyond previous models by including interactions within the local host population that arise as a result of indirect competition between different strains of the pathogen for available hosts: this competition is influenced by the history of infection and, therefore, by the patterns of immunity within the host population.
Instead, they suggest that both are hybrid populations that arose after Europeans arrived in North America, when gray wolves that managed to survive hunting and habitat loss mixed with expanding populations of coyotes.
Whole-cell mass spectrometry fingerprinting could efficiently distinguish monocytic sub-populations that arose from a same hematopoietic lineage.
High frequencies of regions of homozygosity are more common in populations that arose from small founder group, such as the Ashkenazi Jewish population from which these hESC lines were derived.
It is also not known whether MSCs that form the HSC niche also generate other stromal cells or are a specialized population that arises earlier in embryogenesis and persists into adulthood.
Zebrafish melanocytes arise from a small number of bipotent melanogenic progenitors that are derived directly from the neural crest without a stem cell intermediate during the first three days of development, and from another population that arises via an MSC intermediate (Budi et al., 2011; Dooley et al., 2013; Hultman et al., 2009; Tryon et al., 2011).
Populations that arise from just a few individuals, however, tend to have members that share a relatively high percentage of DNA a lack of genetic diversity that can strip them of the evolutionary resources that they may someday need to respond to a deadly new disease, a change in climate, or some other challenge.
In order to characterize the global gene activity correlated with each particular stage of neural development, the full transcriptome of different cell populations that arise during the in vitro differentiation protocol was determined by microarray analysis.
