include a measure that is not associated with significant variance in EXT. Given the depth of information contained in the genetic code, we submit that the latter approach may be the more fruitful one 1) in terms of efficiency, and 2) because the genetic etiology of the individual measures themselves is also of interest. Including all the measures regardless of their gender-specific association with EXT may, nonetheless, yield interesting results. Further research is necessary to address these gender-specific issues.
