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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

NO BLUEPRINT EXISTS. “Even when we add in the regulatory and non-coding regions, there is no program in the genome in the sense that the sequences could be parsed in the way in which we would analyse a computer program to work out what it is specifying. The reason is that crucial parts of the program are missing.” http://rsfs.royalsocietypublishing.org/content/2/1/55 View in LinkedIn

KITCHEN OF TEMPLATE PLATTERS. “The protein-coding sequences are templates. They determine which set of proteins the organism has to play with, just as a child knows which pieces of Lego or Meccano she has available for construction. Those parts of the genome are best regarded as a database.” http://rsfs.royalsocietypublishing.org/content/2/1/55 View in LinkedIn

CATHEDERAL ORGAN. “This metaphor has its limitations. There is no ‘organist’. The ‘music of life’ plays itself, rather as some musical ensembles perform without a conductor. And, of course, the ‘organ’ varies between individuals in a species.” http://rsfs.royalsocietypublishing.org/content/2/1/55 View in LinkedIn

ABSURD PROPOSITION. “To think that the genome completely determines the organism is almost as absurd as thinking that the pipes in a large cathedral organ determine what the organist plays. Of course, it was the composer who did that in writing the score, and the organist himself who interprets it.” http://rsfs.royalsocietypublishing.org/content/2/1/55 View in LinkedIn

DEPENDENT GENES. “The genome as ‘an organ of the cell’. And so it is. DNA sequences do absolutely nothing until they are triggered to do so by a variety of transcription factors, which turn genes on and off by binding to their regulatory sites, and various other forms of epigenetic control, including methylation of certain cytosines and interactions with the tails of the histones that form the protein backbone of the chromosomes. All of these, and the cellular, tissue and organ processes that determine when they are produced and used, ‘control’ the genome.” http://rsfs.royalsocietypublishing.org/content/2/1/55 View in LinkedIn

GREATER THAN GENES ALONE. “The circuits for major biological functions necessarily include non-genome elements. That fact already tells us that the genome alone is far from sufficient.” http://rsfs.royalsocietypublishing.org/content/2/1/55 View in LinkedIn