China 
Africa 
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Bias, Conflict of Interest, Ignorance, and Uncertainty
Published in Ted W. Simon, Environmental Risk Assessment, 2019
The phenotypic fate of developing cells depends on activation of coordinated programs of gene expression during the appropriate time window. The state of chromatin is a significant factor in enabling these programs to occur. DNA methylation, histone alteration, and movement of chromosomes within the nucleus to bring appropriate genes into the transcription compartment all play a role.24–28 Epistasis occurs when the expression of a gene at a specific locus is dependent on the ongoing genetic background: in other words, the interaction between different genes that affects gene expression. Epistasis occurs during both normal development and tumorigenesis.29,30 The use of big data on gene expression and machine learning is revealing epistatic interactions underlying a variety of diseases.31 Cancer cells rely more heavily on glycolysis than on oxidative phosphorylation for their energy needs, and in terms of energetics, resemble single-celled organisms during the early history of the earth when oxygen was absent. As life on earth evolved, the transition to aerobic metabolism also occurred, with the concomitant development of anti-oxidant systems to prevent the toxicity of reactive oxygen species generated by aerobic metabolism. Unlimited growth capacity was a feature of these early organisms, and is shared with cancer cells.32
Posthumanism: Creation of ‘New Men’ Through Technological Innovation
Published in The New Bioethics, 2021
Epistasis is an important phenomenon in the interaction between genes wherein the effect of one gene is dependent on the presence of one or more modifier genes, forming the genetic background. In diploid organisms like human beings, epistasis is further complicated by the presence of two copies of each gene, if they are different, in addition between epistasis between loci, it can occur also between the two copies of each locus. Epistasis can affect phenotypes, by obscuring the effects of a gene when an allele at one locus can mask the effects of alleles at one or more other loci, or by combining gene effects when an allele at one locus modifies the effects of alleles at one or more other loci and produce an entirely new trait (Miko 2008).
Transhumanist Genetic Enhancement: Creation of a ‘New Man’ Through Technological Innovation
Published in The New Bioethics, 2021
Two important difficulties in correlating genes with traits are: (i) the association of more than one gene with a particular trait, and (ii) the association of a gene with more than one trait. Epistasis is a phenomenon in which the presence of one or more ‘modifier genes’ affects the expression of one gene (locus); that is, the expression of the latter is dependent on the genetic background.