Further it seems that this test has been done, though removing only a portion of the junk DNA: http://www.ncbi.nlm.nih.gov/pubmed/15496924

--that was interesting. If the New York Timesy claim that our 3 billion base-pairs of "junk DNA" is filled with a "switchboard" with 4 million switches... which would be on average one switch per 750 base pairs... then this experiment where they removed a 1.5 Mbp and an 0.85 MBp region from junk mouse DNA, then the resulting mice grew up and seemed to be fine... would have removed an expected number of over 2000+1000 of those "switches." Kind of like if you randomly zapped two swaths of 2000 and 1000 transistors from an early computer with 4 million in all. Would that leave the computer apparently working fine? Even if those computer designers had tried to design it to be robust against faults (which they mostly did not), still, this amount of fault tolerance would be pretty impressive. So the 4M switches in our DNA if there, must either be very nonuniformly distributed, or very unimportant, or part of an extremely fault-tolerant circuit. If, in contrast (to compare with the genes in DNA, traditionally regarded as non-junk), you randomly zapped one gene per thousand in your set of about 25K genes (total zappage: 25 of your genes) then what? Would you be fine? 1. This question was examined for a bacterium, not a human: http://en.wikipedia.org/wiki/Mycoplasma_laboratorium this bacterium, one of the smallest genomes known, had 475 genes but they synthesized replacement DNA with fewer genes trying to find a minimal survivable subset. (Actually this bacterium is an obligate parasite i.e. cannot really survive on own without help, but whatever.) They got it down to 382. So it seems 80% of this bacterium's genes are vital. Another measure is this: apparently almost every (apparently over 90%) mouse gene, has an analogous gene inside humans. This suggests that most mammal genes are important, otherwise they'd have vanished & appeared a lot more during mammal evolution. It suggests randomly zapping 25 of your genes, would likely kill you. 2. In http://en.wikipedia.org/wiki/Knockout_mouse it is stated that "While knockout mouse technology represents a valuable research tool, some important limitations exist. About 15 percent of gene knockouts are developmentally lethal, which means that the genetically altered embryos cannot grow into adult mice." So about 1 in 7 of mouse genes are so important that zapping just that one gene, will kill it. Zapping 25 genes would almost certainly kill it. So it looks like genes really are way more crucial than junk. -- Warren D. Smith http://RangeVoting.org <-- add your endorsement (by clicking "endorse" as 1st step)