RT Journal A1 Dorus E T1 IMportance of studying gene-environment interactions psychiatric disorders-reply JF Archives of General Psychiatry JO Archives of General Psychiatry YR 1979 FD June 1 VO 36 IS 6 SP 721 OP 721 DO 10.1001/archpsyc.1979.01780060111016 UL http://dx.doi.org/10.1001/archpsyc.1979.01780060111016 AB In Reply.—  The response by Drs Matthysse and Kidd has assisted me in the clarification of what I had wished to communicate. First, I quoted Lewontin to indicate that I do not restrict my interpretation of gene-environment interactions to the analysis of variance. I focused on an analysisof-variance model because I think that it can be fruitfully applied to the study of the etiology of psychiatric disorders.In citing our second point of disagreement, my argument was not correctly stated. I had said that "to the extent that gene-environment interactions play a more substantial role in psychiatric than in medical disorders, traditional genetic strategies for the study of the etiology of the former are not suitable." We do not know to what extent gene-environment interactions are critical in various subtypes of psychiatric disorders or in effecting a psychiatric disorder in a particular individual. Therefore, I think it is useful to make