G. W. BEADLE 



for the future. But there can be no doubt that the years that lie 

 ahead will be exciting ones in this field. The work of Avery and his 

 co-workers (3) on the transformation of types in Pneumococcus and that 

 of Emerson (13) and of others suggests that we may one day learn to 

 direct gene mutations in predetermined ways. Work on enzymes (32) 

 and viruses (5,46) is so closely related to the general problem of gene 

 structure and gene action that only short steps appear to be necessary 

 to bridge the gaps that separate them. Nucleic acid certainly plays 

 an important role in gene action and in protein synthesis (34,39,40), 

 and it is not too much to hope that this role will be made clear in the 

 near future. The relation of genes to cytoplasmic elements is not well 

 understood, but after many years in which discouragingly little prog- 

 ress has been made, important leads are being followed by Sonneborn 

 (42), Spiegelman (43), and others. After half a century of growth, 

 genetics seems to be assuming a position in the broad field of biology 

 in which its close relations to evolution, development, physiology, and 

 biochemistry are now more evident. 



References 



(1) Alexander, J., and Bridges, C. B., in Colloid Chemistry. Vol. II, Chemical 

 Catalog Co., New York, 1928. 



(2) Atwood, S. S., and Sullivan, J. T., J. Heredity, 34, 311 (1943). 



(3) Avery, O. T. F., McLeod, C. M., and McCarty, M., J. Exptl. Med., 

 79, 137 (1944). 



(4) Bateson, W., MendePs Principles oj Heredity. Cambridge Univ. Press, 

 London, 1909. 



(5) Bawden, F. C, Plant Viruses and Virus Diseases. Chronica Botanica, 

 Waltham, 1943. 



(6) Beadle, G. W., Physiol. Revs., 25, 643 (1945). 



(7) Beadle, G. W., Chem. Revs., 37, 15 (1945). 



(8) Beadle, G. W., and Tatum, E. L., Proc. Natl. Acad. Sci. U. S., 27, 499 

 (1941). 



(9) Corkill, L., N. Zealand J. Sci. Tech., B23, 178 (1942). 



(10) Darlington, C. D., Nature, 154, 164 (1944). 



(11) Delbruck, M., Cold Spring Harbor Symposia Quant. Biol, 9, 122 (1941). 



(12) Delbruck, M., in Advances in Enzymology, Vol. II. Interscience, New 

 York, 1942, p.l. 



(13) Emerson, S., Proc. Natl. Acad. Sci. U. S., 30, 179 (1944). 



(14) FoUing, A., Z- physiol. Chem., 227, 169 (1934). 



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