SEROLOGICAL REACTIONS AS A PROBABLE 

 CAUSE OF VARIATIONS 



PROFESSOR M. F. GUYER 

 University of Wisconsin 



With an insight that has never been surpassed even 

 to this day Claude Bernard,^ more than forty years ago, 

 remarked that " Organic synthesis, generation, regenera- 

 tion, maintenance, and healing of wounds, are different 

 aspects of an identical phenomenon," the phenomenon 

 alluded to being the constructive activity manifested in 

 ordinary nutritive processes. In a recent thoughtful 

 paper, R. S. Lillie- reiterates and expands this point of 

 view. That synthetic metabolism constitutes the very 

 essence of embr>'onic development and therefore of the 

 expression of heredity, scarcely admits of a doubt. To- 

 day it is a truism to say that the visible characters " 

 we deal with in heredity are but the effects— by-products 

 as it were — of far-reaching metabolic reactions. And 

 since the metabolism of the actual living protoplasm cen- 

 ters, if not exclusively, at least principally, in the pro- 

 teins, the problems of metabolism, growth, reproduction 

 and heredity become largely the problem of why and 

 how a given kind of living protoplasm builds up proteins 

 of its own specific type. 



The molecules of the ordinary native proteins are, as 

 is well known, huge polymeric structures of extremely 

 complex constitution. By appropriate chemical treat- 

 ment they ma}^ be broken down into successively smaller 

 and smaller units, each of which, however, still ivs])(mu1s 

 to the ordinary qualitative tests for i)i()ttMtis. Tliere 

 finally comes a point below which furtluM- ic.lu.-tioti of 

 the molecule results in tlu' loss of tlie (listiiid ivc i-rotfin 

 reaction, and tlio oiitcomc is a scries of iiltiinnte char- 

 acteristic units, the aniiiio-acids. Tliii> native i)i'(»teiiis 

 seem to be built up of two different cateuorie- of units: 

 first, combinations of various amino-acids wliidi eoii>ti- 

 tute the simplest protein blocks; and second, the .•.>nil)ina- 

 tion of these into the much larger molecules characteristic 

 of the native proteins. 



1 "Lwona sur les phenomtmes de la vie," Vol. II, p. 517. 

 2BwL Bull., XXXIV, 2, 1918. 



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