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There is nothing intrinsic to DNA methylation itself that requires it to repress transcription. Simply, it affects sequence recognition by proteins. CpG methylation can prevent transcription factor binding and/or recruit proteins that inhibit transcription, either competitively or through chromatin condensation. This is why it's generally associated with ...


1

Tumor cells can have very unstable genomes, as much of the error repair machinery is damaged or missing. Since the cells are rapidly dividing and the DNA gets duplicated each time a cell splits, more and more mutations accumulate as the tumor grows and metastasizes. Just like in evolution as a whole, mutations that are either neutral or help the cell survive ...


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One trivial situation in which this can happen is when the tissue used for expression studies is heterogeneous. Different cells express different levels of the gene. Bimodality can be observed when the system can actually occupy two stable states; i.e. a gene can either have a high expression or a low expression. When you sample the population you would ...


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A group of tightly linked genes that are involved in similar molecular pathway are called supergenes. For the pleasure to formulate a slight opposition to @shigeta's answer, I will give some examples of supergenes in eukaryotes. In Primula, heterostyly is controlled by a supergene. In Papilio memno, mimicry is controlled by a supergene. In some species of ...


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TL;DR: Ubiquitin. Occasional occurrence of paternal inheritance of mtDNA has been suggested in mammals including humans. Clearly, spermatozoa have mitochondria; they make the energy needed for motility. Paternal mitochondrial DNA (mtDNA) does enter oocytes. It is a persisting fallacy that only maternal mtDNA is present in humans because only oocyte ...


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...would then be his offspring at risk? Why? No. Generally speaking, fathers do not pass on their mtDNA (Mitochondrial DNA). Why? Because the mitochondria present in oocytes (egg cell) is the mother's, as every oocyte directly inherits the mother's mitochondria when they are made in the reproductive organs. The mitochondria that the sperm from the ...


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There are many other methods that are used for transfecting cells in culture. These include: Cationic lipid mediated (as mentioned by user137) Calcium Phosphate mediated transfection Biolistic methods Electroporation Newer techniques include optical transfection (using lasers to bore a hole through membrane) and impalefection (using nanotubes). Wikipedia ...



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