Moss - What genes cant do - 2003 (522929), страница 50
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Quoted in (and translated from the fifth Scholium of von Baer’s Entwickelungsgeschichte by) Frederick Churchill (1991).10. The separation of the soma from the germ line in development is only foundin “higher” organisms and so is itself a product of evolution, not a basic characteristic of evolution. See Buss (1987) for an excellent discussion of this.11. The word evolution is derived from the Latin evolvere which means to“unfold or disclose.” Its use in biology begins with that of seventeenth-centurypreformationists for whom development consists of the unfolding or scrollingout of parts always already formed.
The first such use was by Albrecht von Hallerin 1744. Through the eighteenth-century “evolutionism is synonymous with preformationism.” See Richards (1992) for an historical reconstruction of the changing usage of “evolution” with an appreciation for the continuities of its meaning.12. De Vries didn’t speak of “macro” mutations, but by “mutation” he meanta change of structure sufficiently monumental such as can result in a new species.In the terms of current usage, De Vries’s mutation would have to rank as a“macromutation.”13. Penetrance refers to the statistical frequency with which a trait is expressedat all given the presence of the genotype.
Expressivity refers the degree to whicha trait is expressed, given the genotype. These terms were introduced by O. Vogtin 1926 (see Sarkar 1999).14. The Whitehead Institute for Biomedical Research acknowledged in a pressrelease (5/14/2001) that only 1 to 5 percent of cloned animals survive to adulthood (see http://www.sciencedaily.com/releases/2001/05/010511073756.htm).Cloned animals and the placenta that nourish them are typically “dramaticallylarger” than normal couterparts, are frequently riddled with birth defects, anddie hours after birth. The possible longer terms defects of cloning techniques onNotes to pages 42–108201longevity and long-term health cannot be discerned anytime soon as the first successfully cloned animals (such as “Dolly”) are as yet a long ways from naturalold age. (As this book is being prepared for press, national network news hasreported that Dolly—the first cloned sheep—presently 5 years old, has been diagnosed with arthritis.
There is no comment yet on the cause of Dolly’s prematurecondition.) Where cloning technique relies on the juvenescent state of the donorcytoplasm, i.e., an egg cell cytoplasm, “cloners” have been less than forthcoming—to say the least about the potential difficulties of “rejuvenating” the donornucleus.15. To result in a phenotypic difference requires viability, amongst other things,therefore there are a great many possible deviations from sequence norms whichdo not show up as Genes-P because they are not compatible with viability at all,as well as a great many other possible deviations from sequence norms that donot show up as Genes-P because the organism develops and functions withoutnoticeable difference.
See discussion of transgenic animals in chapter 4 for furtherelucidation of this point.Chapter 21. The current number of observed cystic fibrosis mutations can be found, alongwith a great deal of additional information, at the Cystic Fibrosis Mutation DataBase (http://genet.sickkids.on.ca/cftr/).2. Schrödinger did not introduce the term “translation,” and I agree with LilyKay (2000) that the word itself follows from a linguistic-informational theoretictrend independent of Schrödinger; yet, I think it is still compelling thatSchrödinger laid a conceptual groundwork which requires some new means ofbridging a kind of chasm and that turning it into a semantic chasm becomes apossible way to go.Chapter 31.
A heterodimer is a molecular unit composed of two distinct components asopposed to a homodimer, which is composed of two of the same molecules. Thecomponents of a heterodimer are typically referred to as alpha and betasubunits.2. For reference to the theoretical underpinnings of “dissipative systems” seePrigogine (1980) in the reference section. Amongst those working within aDarwinist framework and seeking to reconcile Darwinian evolution with thedynamics of nonequilibrium chemical systems Depew and Weber have been inthe forefront (see Depew & Weber 2001, Depew & Weber 1998, Weber &Depew 1996, and Depew & Weber 1995).3.
The estimate of the number of kinsases in the human genome reported byCelera (Venter et al. 2001) is about half of that reported by Hunter (1995).202Notes to pages 113–1844. Human females have two X chromosomes in the nucleus of every cell, butin each cell one of the two are condensed into permanently inactivated“Barr bodies.” The X chromosome (maternal or paternal), which is inactivated,is variable from cell to cell.5. This quote is taken from the “executive summary” of Oyama, Griffiths, andGray (2001).Chapter 41. Evidence for this and other industrial sources of carcinogenesis was not welldocumented until a century later (Triolo 1965).2.
Aneuploid cells have an irregular number of chromosomes; they are neitherconsistently diploid nor haploid and are generally prone to be unstable.3. Harris’s point here is that in order to distinguish between a dominant and arecessive allele there must be two alleles present at the relevant locus. However,in an aneuploid cell one cannot do this because one cannot presume the presence of the second chromosome. This problem is further intensified by thepropensity for unknown chromosomal-genetic alterations to take place duringthe transfection process.4. Any region of DNA which is deemed to be a gene resides on one of twostrands of the double helix.
Opposite the gene on its complementary strand willbe a sequence of DNA, which consists of all the complementary base pairs tothat of the gene. This is what would be meant by the gene in the anti-senseconfiguration.5. The codons for such an allele would of course always be present as they arejust the complement of the codons of the fibronectin allele. What would constitute the formation of an anti-sense “allele” would have to be the acquisition ofupstream promoter sequences that bind the polymerase complex and allow theanti-sense codons to show up as a transcriptional unit.6.
Soluble proteins released by white blood cells.7. Mantle’s father and grandfather had died in their early forties of Hodgkin’slymphoma.8. A quite sympatico analysis can be found in The Society of Cells (Sonnenschein& Soto 1999) which can also be used as a kind of primer on carcinogenesis.Chapter 51. The first use of the word biology was by Karl Friedrich Burdach in 1800 torefer to the study of man from a zoological perspective. In 1802 Gottfried Reinhold Treviranus and Jean-Baptiste Lamarck both used it with its current meaningimplied (Richards 2000).Notes to pages 184–1962032. I take this apt description from the title of Evelyn Fox Keller’s book (Keller2000).3.
Perhaps the most rigorous and intellectually honest attempt to salvage aminimal preformationism based upon an analysis of the scope of coding is thatof Godfrey-Smith (2000).4. Consider for example that what enables the cow to digest grass and thetermite to digest wood is not an evolved autochthonous capacity but the factthat they each house a protazoan which in turn houses a bacteria that possessesthe cellulase enzyme. Enzymatic capabilities that were “left behind” in the bacteria world a billion years ago are not reinvented.5.
For a discussion of competing theories of the origins of life see Moss 1998.6. Lynn Margulis is responsible for establishing the symbiotic basis of theevolution of the eukaryotic cell, among many other things (see Margulis 1981,1996).7. Individuals with no more than 29 CAG repeats do not appear to suffer diseasesymptoms. Most individual’s who present with the disease have been seen tohave between 40 and 55 repeats, with over 70 repeats being rare, but over 100repeats occassionaly observed (see http://www.bcm.tmc.edu/neurol/struct/hunting/huntp3.html and related articles on the HD Clinic website for currentfindings).8.
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