Genie and Non-genic Parts of the Chromosome 53 



and the phenocopic action of the ion succeed in changing the pheno- 

 type by inhibiting the same enzyme function. Let us assume that 

 the transformer acts as a phenocopic agent upon the bacterian cell, 

 which implies that the genie material is not involved. (One might 

 speak of Dauermodifikation; see discussion below.) The first pre- 

 requisite of such a process would be that the effect be visible only 

 within a clone (which corresponds to a multicellular organism) and 

 end with a sexual phase. It may be said that no sexual phase is 

 known in pneumococci; in E. coli, where the assumption of a sexual 

 phase is unavoidable, the transformation experiments gave "irregular" 

 results (Boivin, 1945), facts which might provide some clue. The 

 important point is that the DNA extract produces the phenotype of 

 its own origin, while the action of a metal ion in phenocopy experi- 

 ments has no relation to the origin of the agent. If in the bacterium 

 the mutant effect consisted in an effect upon a certain enzyme action 

 (as in Drosophila), and ff this effect were produced by some deriva- 

 tive of a certain DNA, the introduction of the same DNA into a cell 

 could lead to a specific phenocopic action. The fact that depolymeri- 

 zation of DNA in vitro prevents the transformation action may or may 

 not militate against this possibility. I think that this type of argu- 

 ment which can be put to experimental test should not be over- 

 looked, whatever the difiiculties at the present moment and however 

 vague it appears thus far. 



In view of the caution we adopted in the interpretation of the 

 important facts we may now quote some more optimistic views. 

 Haldane ( 1954 ) , after a calculation of the molecular species supposed 

 to be present in a bacteriophage and available for chemical isolation, 

 declares: "On the other hand, the purification of a transforming princi- 

 ple may be simpler. But it is perhaps in these simple organisms that 

 the material basis of inheritance will first be specifiable in chemical 

 terms." But on the next page we read: "There is no reason to expect 

 a priori that the general principles of genetics should hold for bac- 

 teria. If some of them do so, that is very satisfying, but it seems 

 equally unwise to argue, except in the most tentative way, from 

 bacterial mutations to mutations in other organisms, or from non- 

 Mendelian behavior in bacteria against Mendelian behavior in other 

 organisms." 



dd. Some additional relevant facts 



It is known that RNA is somehow produced by the DNA in 

 the chromosomes, deposited in the nucleolus (see, however, Ham- 



