FINE STRUCTURE OF A GENETIC REGION IN BACTERIOPHAGE 



By Seymour Benzer 



BIOPHYSICAL LABORATORY, DEPARTMENTS OF BIOLOGICAL SCIENCES AND PHYSICS, 

 PURDUE UNIVERSITY, LAFAYETTE, INDIANA 



Communicated by M. Delbriick, April 6, 1955 



This paper describes a functionally related region in the genetic material of a 

 bacteriophage that is finely subdivisible by mutation and by genetic recombination. 

 The group of mutants resembles similar cases which have been observed in many 

 organisms, usually designated as "pseudo-alleles." (See reviews by Lewis^ and 



Reprinted by permission of the author and the National Academy 

 of Sciences from the Proceedings of the National Academy of 

 Sciences, 41 (6), 344-354, June, 1955. 



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