The Linear Arrangement of Six Sex-Linked 

 Factors in Drosophila, as Shown by Their 

 Mode of Association 



A. H. STURTEVANT 



Reprinted by author's and publisher's permission 

 from Journal of Experimeiital 7.oology, vol. 14, 

 1913, pp. 43-59. 



Sturtevanf s paper takes advantage of the previous researches of 

 many differejJt people, adds to them a series of detailed experiinetits, 

 a?id results in defi?iite proof that the factors (genes) are arranged 

 in a linear sequence alo?ig the chrofnosome. Actually, Sturtevant 

 regarded his work as a substa?itiatio7i of the hypothesis that the genes 

 were carried by the chromoso?Jtes, pri??mrily as a consequence of the 

 linear fiattire of their arrangeineiit, for the only possible iJiethod of 

 lijiear arrajigeinejit withifi a cell would be along the length of the 

 chromosome. 



The work provided the basis for the co7istruction of chromosome 

 maps i?i many species besides Drosophila, because the ?nethod used is 

 applicable iti any species in which linkage groups have been dis- 

 covered. It should be kept in mifid that these are proportioTial loca- 

 tiojjs, and therefore show o?ily relative, not actual, positiofis. 



Sturtevanfs paper is brief, concise, and to the point. It has the 

 added virtue of careful presejitatio?i of the problems created as a 

 conseque?Jce of the research, and the ajjalysis of possible objections 

 to the residts. Carefzd study of this paper will greatly repay anyone 

 i?iterested m the tech?iique of presejitatio?i of research residts. 



historical 



The parallel between the behav- 

 ior of the chromosomes in reduction 

 and that of Aiendelian factors in segre- 

 gation was first pointed out by Sutton 

 ('02) though earlier in the same year 

 Boveri ('02) had referred to a possible 

 connection (loc. cit., footnote 1, p. 



81). In this paper and others Boveri 

 brought forward considerable evi- 

 dence from the field of experimental 

 embryology indicating that the chro- 

 mosomes play an important role in 

 development and inheritance. The first 

 attempt at connecting any given so- 

 matic character with a definite chro- 

 mosome came with McClung's ('02) 



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