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CELL SPECIFICITY WITH SINGLE CODE. “Which proteins and RNAs are made when and where is not fully specified. This is why it is possible for the 200 or so different cell types in an organism such as the human to make those cell types using exactly the same genome. A heart cell is made using precisely the same genome in its nucleus as a bone cell, a liver cell, pancreatic cell, etc.” http://rsfs.royalsocietypublishing.org/content/2/1/55 View in LinkedIn

READ-ONLY VERSUS READ-WRITE. “But the genome is not a fixed program in the sense in which such a computer program was defined when Jacob and Monod introduced their idea of ‘le programme génétique’. It is rather a ‘read–write’ memory that can be organized in response to cellular and environmental signals.” http://rsfs.royalsocietypublishing.org/content/2/1/55 View in LinkedIn

TEMPLATED WORLD. “So what does the genome cause? The coding sequences form a list of proteins and RNAs that might be made in a given organism. These parts of the genome form a database of templates.” http://rsfs.royalsocietypublishing.org/content/2/1/55 View in LinkedIn

APPARENT GENE PRIMACY. “The sequences of DNA triplets form templates for the production of different amino acid sequences in proteins. Amino acid sequences do not form templates for the production of DNA sequences. That, in essence, is what was shown. The template works in only one direction, which makes the gene appear primary.” http://rsfs.royalsocietypublishing.org/content/2/1/55 View in LinkedIn

CENTRAL DOGMA OF MOLECULAR BIOLOGY. “The essence of the central dogma is that ‘coding’ between genes and proteins is one-way.” http://rsfs.royalsocietypublishing.org/content/2/1/55 View in LinkedIn

METAPHORICAL BIAS. “Does the metaphorical nature of the way we represent upward and downward causation matter? The bias introduced by the metaphor is that there is a strong tendency to represent the lower levels as somehow more concrete. Many areas of science have proceeded by unravelling the small elements underlying the larger ones. But notice the bias already creeping in through the word ‘underlying’ in the sentence I have just written.” http://rsfs.royalsocietypublishing.org/content/2/1/55 View in LinkedIn

CONSENSUS AND EXCEPTIONS. "AP and disposable soma hypotheses are widely accepted as the standard explanations for genetic programs that cause senescence in multicellular organisms. However, there are some results that are in conflict with their predictions." (AP = antagonistic pleiotrophy hypothesis). View in LinkedIn

NO COST TO LONGEVITY. "A recent study of Caenorhabditis elegans reported that selecting for early fecundity did not produce a cost in terms of longevity." View in LinkedIn

REFERENCE FOR TODAY: Are Internal, Death-Promoting Mechanisms Ever Adaptive?" "John W Pepper, Deborah E Shelton, Armin Rashidi, and Pierre M Duran. (This reference refuses to post normally on LI). View in LinkedIn

SO ENDS this first of two weekends with Denis Nobel. Ideas evolve. In recent history, the genome was discovered. In short order, it was sequenced in many species. Then environmental influences were described. And with each step, our understanding of the meaning of the genome has changed. And will continue to do so as new findings occur. View in LinkedIn