Primary diffuse large B-cell lymphomas of the central nervous system are targeted by aberrant somatic hypermutation
This somatic hypermutation
results in a highly responsive pool of B-cells that can be reactivated much more rapidly on the next encounter with their antigen.
Other important features include impaired antigen uptake and presentation of antigen by antigen-presenting cells, lower numbers of naive T cells due to thymic involution and a lower diversity of the T cell repertoire, lower numbers of naive B cells, impaired isotype switching, and somatic hypermutation
, which leads to weaker antibody responses with lower affinity (6).
Epidemiological evidence and indirect molecular findings from immunoglobulin heavy chain variable region gene studies suggest that chronic persistent antigen stimulation constitutes a significant pathogenetic mechanism of thyroid NHL (6), (7) Aberrant activity of somatic hypermutation
is another mechanism which may contribute to the development of lymphoid malignancies by causing genetic instability and favouring chromosomal translocation (8).
The neoplastic cells in PEL lack surface expression of B-cell markers, such as CD19, CD20, CD79a, and immunoglobulin, they express plasma cell-related markers, such as CD30, CD38, CD45, and CD138, but they also exhibit clonal rearrangement and somatic hypermutation
of immunoglobulin genes, suggesting that they originate from post-germinal center B-cells (1), (5), (6), (7).
Among its other findings, this study is the first to find that the genomes of breast carcinomas bear regional clusters of hypermutation
, termed "kataegis," and that these regions display a prevalence of signature B mutations.
2004) have suggested that cellular stress responses might provoke hypermutation
in the roundworm Caenorhabditis elegans.
as a factor contributing to the acquisition of antimicrobial resistance.
The number of clones and hypermutation
operation can be respectively defined as:
Also, biofilm production has been related to the occurrence of genetic events such as hypermutation
, transfer of genes and activation of distinct metabolic pathways.
Meyerhans A, Asjo B, Wain-Hobson S: Selection, Recombination, and G A Hypermutation
of Human Immunodeficiency Virus Type 1Genomes: JV (April) 1991: 1779-1788.
allow the immune system to explore local areas around a specific antibody by making small steps towards an antibody with higher affinity.