A COMMENTARY ON LAMARCKISM 



antigen, there is a possibility that antibodies induced by this 

 antigen may react with the gene/ In other words, the anti-lens 

 serum, in addition to acting directly upon the foetal lens, may 

 have altered in a genetically reproducible way the structural 

 specificity of one or more ''lens genes\ Sturtevant refers to 

 unpublished (and apparently still unpublished) evidence of 

 R. R. Hyde in support of the original authors' claims. 



Guyer and Smithes experiments are plausible in a purely 

 immunological sense, quite apart from the fact that they were 

 done in a period when the authors could hardly have hoped for 

 a genetical benediction. An '"anti-kidney'* or 'anti-mesenchyme'' 

 immune serum would be expected to be quite ineffective, be- 

 cause the immune bodies would be promptly absorbed by the 

 corresponding maternal tissues and so denied access to the 

 foetus. But the lens of adult rabbits is avascular; anti-lens 

 antibodies should not therefore be absorbed by the mother but 

 should be left free to act upon the vascularized lens of the 

 foetus. Nor is there anv doubt that antibodies can reach the 

 rabbit foetus — not through the placenta, as was formerly 

 believed, but through the yolk sac (see Brambell, Hemmings 

 and Henderson, 1951) Unfortunately, there is discrimination 

 against antibodies ("heterologous antibodies'*) formed in an 

 organism of a foreign species, and this, combined with the very 

 decided toxicity of foreign serum as such, makes one regret 

 that Guyer and Smith did not persevere with the experiments 

 in which they tried to elicit anti-lens antibodies from the rabbit 

 itself.* 



We must not, however, be led astray by speculations on 

 whether or not the phenomena described by Guyer and Smith 



* [It has occurred to me, as a possible explanation of Guyer and Smith's 

 positive results, that the lens preparations which they used as antigens 

 may have been contaminated with bacteria. Bacterial antigens are now 

 known to exert a powerfully 'adjuvant' action upon the production of 

 antibodies by simple antigens, and this applies to auto-antibodies as well. 

 See J. Freund, Advances in Tuberculosis Research, 7, p. 130, 1956.1 



93 



