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Comments 



MacKey: It is possible that the extremely positive results obtained by 

 Dr. Gregory in his mutation program in peanuts may partly depend 

 on the fact that he is using a polyploid. 



Genes interact in a very complicated way, and it is no reason to 

 believe that the dosage for each gene in this interaction should be opti- 

 mal on the level brought about by a more or less complete reduplica- 

 tion of the somatic chromosome set. A more subtle adjustment may just 

 as well go via loss, inactivation, duplication, and gene diversification. 



