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EPIGENETICS. "The term epigenetics refers to heritable changes in gene expression (active versus inactive genes) that does not involve changes to the underlying DNA sequence; a change in phenotype without a change in genotype. This in turn affects how cells read the genes. Epigenetic change is a regular and natural occurrence but can also be influenced by several factors including age, the environment/lifestyle, and disease state." https://lnkd.in/eVaRKtt View in LinkedIn

NOT GENE MUTATION. "Epigenetics” refers to covalent modification of DNA, protein, or RNA, resulting in changes to the function and/or regulation of these molecules, without altering their primary sequences. In some cases, epigenetic modifications are stable and passed on to future generations, but in other instances they are dynamic and change in response to environmental stimuli." https://lnkd.in/ewQi_y7 View in LinkedIn

Near Galway this weekend. Priceless. View in LinkedIn

SO ENDS convergent evolution until next weekend. Seemingly improbable, it highlights the importance of selective pressures on an organism finding the best solution; that very different organisms find very similar solutions to selective pressures despite vast structural differences remains one of the fascinating aspects of the topic. It also reveals, surprisingly, that whole phenotypes sometimes may be controlled by only a few genes. View in LinkedIn

MOLECULAR EVOLUTION. "Thus, it appears that resistance to snake venom α-neurotoxin has evolved at least four times among mammals through two distinct biochemical mechanisms operating at the same sites on the same receptor." http://www.sciencedirect.com/science/article/pii/S0041010115000690 View in LinkedIn

TOXIN RESISTANCE. "The muscular nicotinic cholinergic receptor (nAChR), targeted by snake α-neurotoxins, has evolved in some venom-resistant mammals to no longer bind these toxins. Through phylogenetic analysis of mammalian nAChR sequences, we show that honey badgers, hedgehogs, and pigs have independently acquired functionally equivalent amino acid replacements in the toxin-binding site of this receptor." http://www.sciencedirect.com/science/article/pii/S0041010115000690 View in LinkedIn

SCALLOP TYPES. "Our results demonstrate that five of the six life habit types exhibited by scallops have evolved multiple times. We identified 17 repeated transitions between life habit classes within the Pectinidae that were the result of both parallel and convergent evolution." http://bmcevolbiol.biomedcentral.com/articles/10.1186/1471-2148-11-164 View in LinkedIn

CONVERGENCE. "Phytoplasmas are pathogenic bacteria that reprogram plant development such that leaf-like structures instead of floral organs develop. Infected plants are sterile and mainly serve to propagate phytoplasmas and thus have been termed ‘zombie plants’. We suggest that SAP54 underwent convergent sequence evolution to mimic the K-domain of its targets. This enabled it to interact with its MADS-domain protein targets and thereby manipulate plant development to its own benefit." https://lnkd.in/eJF3hwd View in LinkedIn

PARALLEL HIV LINEAGES. ""Some pathogens exhibit striking parallel genomic changes, including multiple HIV lineages that substituted similar mutations conferring antiviral drug resistance and several strains of Escherichia coli that independently acquired similar virulence factors by horizontal transfer." http://www.pnas.org/content/103/24/9107.full View in LinkedIn

SELECTION DRIVEN. "Both parallel evolution and convergent evolution provide strong evidence that the derived similarities resulted from adaptation by natural selection, provided the state-space of possible changes is so large that it is improbable that the observed similarities arose by a purely random process." https://lnkd.in/exArCm7 View in LinkedIn