overdominance

Although our work does not provide a unique prediction that will differentiate between overdominance versus sexual antagonism in all cases, it does identify diagnostic patterns.

The Volokh Conspiracy » There’s Always Next Year 2009

Limitations and complications of the theory include changes in environment or genetic background, enzymes with sharply defined optima of activity, overdominance, pleiotropy, multifunctional enzymes and branched metabolic pathways.

Darwin and neutrality - The Panda's Thumb 2007

An example of overdominance is the allele in black Africans that confers resistance to malaria when present in one chromosome (heterozygous), but causes sickle cell anemia when present in both (homozygous).

"The more we play God or try to improve on Mother Nature, the more damage we are doing with all kinds of experiments that... turn into nightmares." Ann Althouse 2007

I'm aware of three current theories, although sitting here, drinking, I can only think of two, and of those two, only one interests me; it's called overdominance.

"The more we play God or try to improve on Mother Nature, the more damage we are doing with all kinds of experiments that... turn into nightmares." Ann Althouse 2007

Coding variation did not introduce any new sign motifs, but the sign motifs belonging to negative autoregulation generated negative as well as positive overdominance (see below for further discussion of overdominance).

PLoS ONE Alerts: New Articles Arne B. Gjuvsland et al. 2010

Positive autoregulation with no coding variation generated about the same proportion of overdominance for the sign motifs [0 0 +], [0 + +]

PLoS ONE Alerts: New Articles Arne B. Gjuvsland et al. 2010

B framework is quite restricted when it comes to explaining why recessive mutants are so common, the appearance of dominant mutations, the existence of functional recessive homozygotes, the phenomenon of overdominance, and how genetic dominance may arise from intralocus interaction

PLoS ONE Alerts: New Articles Arne B. Gjuvsland et al. 2010

But considering the role overdominance is supposed to have in connection with generation of heterosis the results suggest that the allele interaction concept and the associated sign motifs may contribute to a better understanding of the heterosis phenomenon.

PLoS ONE Alerts: New Articles Arne B. Gjuvsland et al. 2010

We analyzed the single locus case in more detail to identify which of the realized allele interaction sign motifs were most prone to generate overdominance compared to partial or complete dominance.

PLoS ONE Alerts: New Articles Arne B. Gjuvsland et al. 2010

Frequencies of partial dominance/additive gene action (red bars) and overdominance (blue bars) for autoregulation with nonmonotonic dose-response relationship.

PLoS ONE Alerts: New Articles Arne B. Gjuvsland et al. 2010