Alvarez G, Zapata C
Departamento de Biología Fundamental, Facultad de Biología, Universidad de Santiago de Compostela, Spain.
Genetics. 1997 Jun;146(2):717-22. doi: 10.1093/genetics/146.2.717.
Conditions for protected inversion polymorphism under the operation of both karyotype and supergene selection in a viability model have been analytically determined. When supergene selection (the effect of recombination in homokaryotypes lowering the mean fitness of their offspring) is acting on gene arrangements and there is no karyotype selection, it is demonstrated that a polymorphic stable equilibrium is reached by the population, which is a function of only the recombination effects in homokaryotypes. Under both supergene and karyotype selection the degree of dominance (h) of karyotype selection is critical to produce a protected inversion polymorphism. In general, the opportunity for protected polymorphism increases as the degree of dominance decreases. For small s values, the conditions for protected polymorphism are r > 2sh and c > 2s(h-1), where r and c are the average loss of viability for offspring of ST/ST and IN/IN homokaryotypes, respectively. These findings suggest that supergene selection may be an important balancing mechanism contributing to the maintenance of inversion polymorphism.
在一个生存力模型中，已经通过分析确定了在核型和超基因选择共同作用下受保护的倒位多态性的条件。当超基因选择（同核型中重组降低其后代平均适合度的效应）作用于基因排列且不存在核型选择时，证明种群会达到一个多态稳定平衡，它仅是同核型中重组效应的函数。在超基因和核型选择共同作用下，核型选择的显性程度（h）对于产生受保护的倒位多态性至关重要。一般来说，随着显性程度降低，受保护多态性的机会增加。对于小的s值，受保护多态性的条件是r > 2sh且c > 2s(h - 1)，其中r和c分别是ST/ST和IN/IN同核型后代的平均生存力损失。这些发现表明超基因选择可能是有助于维持倒位多态性的重要平衡机制。
