I have just started this book by Matt Ridley.
It is very enjoyable and I keep finding little fun nuggets. Here is an example (page 36) regarding teh ASPM gene on on chromosome 1.
quote:
It is a large gene, 10,434 letters long and split into 28 paragraphs(called exons). The 16th to 25th paragraphs contain a characteristic motif repeated over and over again. The phrasse, usually 75 letters long, begins with the code for teh amino acis isoleucine and glutamine, the significance of which I will reveal in a moment. In the human version of the gene, there are 74 just motifs, in the moust 61, in the fruit fly 24 and in the nematode worm just 2 repetitions. Remarkably, these numbers seem to be in proportion to the number of neurons in the adult brain of the animal. Even more remarkably, the standard abbreviation for isoleucine is 'I' and the abbreviation of glutamine is 'Q'. Therefore the number of IQ repeats may determine the relative IQ of the species, which according to Woods, 'is proof of God's existance since only someone with a sense of humour could have arranged for the correlation.'
Fun eh?
ASPM was uncovered in studying families with herediatry small brains (but otherwise normal). It seems to work, according to Ridley, "by regulating the number of times neuronal stem cells divide inside the vesicale of the young brain about two weeks after conception."
He is discussing the regulation of the gene expression. There seem to be many examples of how small changes in promoters can produce large changes in the final result. It is my thought that there may well be fairly sudden jumps in evolutionary changes based on this.
As well as smaller changes of course.
{Fixed quote box - AM}
[This message has been edited by Adminnemooseus, 06-18-2003]
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