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In evolution, it can scramble the information needed to reconstruct the phylogeny of organisms, how they are related to one another. HGT can also help scientists to reconstruct and date the tree of life, as a gene transfer can be used as a phylogenetic marker, or as the proof of contemporaneity of the donor and recipient organisms, and as a ...
The following table is a representative sample of Erwin Chargaff's 1952 data, listing the base composition of DNA from various organisms and support both of Chargaff's rules. [17] An organism such as φX174 with significant variation from A/T and G/C equal to one, is indicative of single stranded DNA.
Evolution by gene duplication is an event by which a gene or part of a gene can have two identical copies that can not be distinguished from each other. This phenomenon is understood to be an important source of novelty in evolution, providing for an expanded repertoire of molecular activities.
Recombination is important as a source of genetic diversity, as a mechanism for repairing damaged DNA, and a necessary step in the appropriate segregation of chromosomes in meiosis. [14] The presence of repeated sequence DNA makes it easier for areas of homology to align, thereby controlling when and where recombination occurs.
Horizontal gene transfer is the primary mechanism for the spread of antibiotic resistance in bacteria, [8] [5] [9] [10] and plays an important role in the evolution of bacteria that can degrade novel compounds such as human-created pesticides [11] and in the evolution, maintenance, and transmission of virulence. [12]
Population structure is an important aspect of evolutionary and population genetics. Events like migrations and interactions between groups leave a genetic imprint on populations. Admixed populations will have haplotype chunks from their ancestral groups, which gradually shrink over time because of recombination. By exploiting this fact and ...
Molecular evolution describes how inherited DNA and/or RNA change over evolutionary time, and the consequences of this for proteins and other components of cells and organisms. Molecular evolution is the basis of phylogenetic approaches to describing the tree of life. Molecular evolution overlaps with population genetics, especially on shorter ...
The structure of the DNA double helix (type B-DNA). The atoms in the structure are color-coded by element and the detailed structures of two base pairs are shown in the bottom right. DNA exists as a double-stranded structure, with both strands coiled together to form the characteristic double helix.