Department of Epidemiology, Emory University, Atlanta, Georgia, USA.
BMC Genet. 2005 Dec 30;6 Suppl 1(Suppl 1):S57. doi: 10.1186/1471-2156-6-S1-S57.
The information content of a continuous variable exceeds that of its categorical counterpart. The parameterization of a model may diminish the benefit of using a continuous variable. We explored the use of continuous versus discrete environment in variance components based analyses examining gene x environment interaction in the electrophysiological phenotypes from the Collaborative Study on the Genetics of Alcoholism.
The parameterization using the continuous environment produced a greater number of significant gene x environment interactions and lower AICs (Akaike's information criterion). In these cases, the genetic variance increased with increasing cigarette pack-years, the continuous environment of interest. This did not, however, result in enhanced LOD scores when linkage analyses incorporated the gene x continuous environment interaction.
Alternative parameterizations may better represent the functional relationship between the continuous environment and the genetic variance.
连续变量的信息含量超过其分类变量的信息含量。模型的参数化可能会降低使用连续变量的优势。我们探讨了在基于方差分量的分析中使用连续与离散环境的方法,该分析检查了酒精中毒遗传学合作研究中电生理表型的基因 x 环境相互作用。
使用连续环境进行参数化会产生更多的显著基因 x 环境相互作用和更低的 AIC(Akaike 信息准则)。在这些情况下,遗传方差随着感兴趣的连续环境——香烟包年数的增加而增加。然而,当连锁分析纳入基因 x 连续环境相互作用时,这并没有导致 LOD 分数的提高。
替代参数化可能更好地表示连续环境与遗传方差之间的功能关系。