Accumulation Of Recessive Mutations Research Articles

Evolutionary Processes in Anthropogenic Biogeochemical Provinces

The role of anthropogenic biogeochemical provinces in modern evolutionary transformations of the organic world is discussed in light of A.P. Vinogradov’s theory. The existence of anthropogenically impacted microevolution follows from numerous facts of changes in biological species at contaminated habitats. The impacts of two key factors on the genetic pool of a population are discussed: the accumulation of recessive mutations and the systematic selection of tolerant genotypes. The tolerance of organisms is demonstrated to be of polygenetic nature, and hence, selection can proceed in a population simultaneously at various loci and alleles. The selection of a resistant genotype weakens the adaptability of the population to other extremal factors of the environment. External factors and the structure of a population control the rate and avenues of the evolutionary transformations.

Heritable colorectal cancer and cancer genes: systemic expressions.

Epidemiological studies of heritable cancer have demonstrated that cancer predisposition is a dominant trait; these studies have also predicted the recessive outcome of the neoplastic process. Biochemical studies of dominantly heritable cancer have demonstrated the relevance of systemic effects. The systemic effects are presumably due to a dominant mutation at the "initiator locus." Collectively they define cancer initiation at the cellular level (as described in this review). Molecular biological studies have demonstrated that cancer progression and the appearance of clinical cancer occur through an accumulation of recessive mutations at critical loci. We must continue to try to define not only the inherited and acquired gene defects that initiate the neoplastic state but also the subsequent genetic alterations and biomarkers involved in tumor progression. These genetic defects are already proving useful in diagnosis and prognostication. The hope is that these biomarkers may be useful for designing specific differentiation therapy.