On 17 Dec 2009 at 22:15, Jim Clark wrote: > > The level of lactose intolerance (in modern times at least) is quite low for > UK (presumably Caucasians?), > which leads one to wonder about its a priori probability as a disorder for > Darwin.
When I said "while he [John Hayman, the author of the recent BMJ article on Darwin's illness] seems to agree that the lactose (or milk protein) intolerance theory does have merit", I wasn't erroneously claiming that lactose is milk protein, because lactose is, of course, milk sugar. But I was too brief to be understandable. What Hayman said in his note to me was that he thought that Darwin may have had an allergy to milk protein rather than to lactose. It's regrettable he couldn't find a place for his views on this in his published paper. > It also allows one to make the point that genetic does NOT > equal immutable, perhaps another factor in student resistance to genetic > hypotheses. I must demur, although perhaps only to the way this is expressed. Genetic causation does mean immutable. It is possible to reduce or prevent the secondary consequences of the genetic specification (a trivial example would be hair dye for people suffering from red hair; a non-trivial example the special diet used to treat PKU) but the genetic basis remains unchanged. It's still red under the blonde hair dye; the individual with PKU still can't metabolize phenylalanine. It is true that we are on the cusp of real genetic change through gene therapy; it may already be here in a few extraordinary cases. But in general, while we can ameliorate the consequences of a genetic specification, we cannot change the specification nor its direct consequence. Cautious note to the red-haired. I joke. I have nothing against red hair. Indeed, some of my best friends have red hair. Stephen ----------------------------------------------------------------- Stephen L. Black, Ph.D. Professor of Psychology, Emeritus Bishop's University e-mail: sbl...@ubishops.ca 2600 College St. Sherbrooke QC J1M 1Z7 Canada ----------------------------------------------------------------------- --- To make changes to your subscription contact: Bill Southerly (bsouthe...@frostburg.edu)
