Pleiotropy. Pleiotropy is the phenomenon whereby a single gene has multiple consequences in numerous tissues. Pleiotropic effects stem from both normal and mutated genes, but those caused by mutations are often more noticeable and easier to study.leiotropy. Pleiotropy is the phenomenon whereby a single gene has multiple consequences in numerous tissues. Pleiotropic effects stem from both normal and mutated genes, but those caused by mutations are often more noticeable and easier to study.
An evaluation instrument is typically a questionnaire, an interview script, or a set of observation guidelines, used to evaluate one or more aspects of an intervention in the drugs field.nstruments are generally classed according to the intervention field they are designed to be used in (treatment, prevention, or harm reduction), though some instruments may be usable in more than one field.
Evaluation is the systematic assessment of the worth or merit of some object. This definition is hardly perfect. There are many types of evaluations that do not necessarily result in an assessment of worth or merit -- descriptive studies, implementation analyses, and formative evaluations, to name a few. Better perhaps is a definition that emphasizes the information-processing and feedback functions of evaluation. Both definitions agree that evaluation is a systematic endeavor and both use the deliberately ambiguous term 'object' which could refer to a program, policy, technology, person, need, activity, and so on.