Tentative Plan for Understanding Genotype and Performance

We should start with the premise that almost every (physical) performance trait will be related to some distinct group of genotypes. (Genotypes from outside the group can also influence the trait, but this does not change the basic premise). This group of related genotypes will usually present itself in the general population as most individuals having average performance, some individuals having below-average performance, and another group of individuals having above-average performance. If we were to take "running" as an example, we can already begin to scientifically relate this trait to genetic polymorphisms in muscle tissue as well as other physiological characteristics. Even though we will ultimately identify the related group of genotypes that can accurately predict the performance level for any given physical trait, several problems do exist. The first problem is that there is considerable complexity in how different traits combine to affect "overall" performance. The second problem is to determine how these combinations of traits influence overall performance under different environmental challenges or stresses.

The goals for an initial plan to evaluate genotype and performance are listed below:

i) Begin to correlate physical (and related behavioral) performance characteristics with the genotypes and polymorphisms that are rapidly emerging from the human genome project. This would not be much different than what pharmaceutical companies are doing related to patient stratification for drug toxicity effects.

ii) Begin to model how combinations of traits influence overall performance. Then separate the groups of directly related genotypes from those that indirectly influence the trait.

iii) Begin to model and understand how a higher performance trait (or traits) that provide(s) an advantage under one set of environmental conditions and/or challenges, is not an advantage or is even a disadvantage under another set of environmental conditions and/or challenges.

This third point is probably the most difficult to deal with, because it leads to diversionary semantic and philosophical questions as to whether biology (genetics) or environment is in control, and what is cause and what is effect. These questions will be put into better perspective using examples of genetic disease in the human population (Jorder et al. 2000) and examples of how particular "types" of stress relate to heart disease (Ridley 2000; Marmot et al. 1991).

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