10 SEX IN MICROORGANISMS 



of five matings has been calculated. Recombination data obtained by 

 Doermann in phage T4 led to the conclusion that if we refer to a 

 single mating no interference can be demonstrated. 



GENERAL CONCLUSIONS 



Bacteriophage can be considered a haploid organism possessing 

 nothing analogous to sex. A theory has been postulated which ac- 

 counts for the recombination data known at present. This theory is 

 supported also by some biological data on the intracellular growth of 

 the bacteriophage. Some predictions of the theory have been verified. 

 One important factor is not explained by the theory: heterozygosis. 

 At the present moment phage looks rather unsuitable for genetic 

 research, because the progeny of a single mating cannot be examined. 

 We are in the situation of a geneticist who can examine his popula- 

 tion once in a while, say once in every five generations. On the other 

 hand, genetics of bacteriophage appears to be a powerful tool in the 

 attempt to explain the main biological features of virus reproduction. 



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Cold Spring Harbor Symposia Quant. Biol., 11, 33-37. 

 Doermann, A. H. 1948. Intracellular growth of bacteriophage. Carnegie Ivst. 



Wash. Yearbook, 47, 176-186. 

 . 1951. Intracellular phage growth as studied by premature lysis. Fed- 

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 Doermann, A. H., and M. B. Hill. 1953. Genetic structure of bacteriophage 



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