Caillaud M C, Boutin M, Braendle C, Simon J-C
Department of Entomology, Cornell University, Ithaca NY 14853, USA.
Heredity (Edinb). 2002 Nov;89(5):346-52. doi: 10.1038/sj.hdy.6800146.
Discrete variation in wing morphology is a very common phenomenon in insects and has been used extensively in the past 50 years as a model to study the ecology and evolution of dispersal. Wing morph determination can be purely genetic, purely environmental, or some combination of the two. The precise genetic determinants of genetically based wing morph variation are unknown. Here we explore the genetic basis of wing polymorphism in the pea aphid, which can produce either winged or wingless males. We confirm that three types of pea aphid clones coexist in natural populations, those producing winged males only, those producing wingless males only, and those producing a mixture of both. A Mendelian genetic analysis reveals that male wing polymorphism in pea aphids is determined by a single locus, two alleles system. Using microsatellite loci of known location, we show that this locus is on the X chromosome. The existence of a simple genetic determinism for wing polymorphism in a system in which genetic investigation is possible may help investigations on the physiological and molecular mechanisms of genetically-based wing morph variation. This locus could also be used in the search for genes involved in the wing polyphenism described in parthenogenetic females and to investigate the interplay between polymorphisms and polyphenisms.
翅形态的离散变异在昆虫中是一种非常常见的现象，并且在过去50年中被广泛用作研究扩散生态学和进化的模型。翅形态的确定可以完全由基因决定，完全由环境决定，或者是两者的某种组合。基于基因的翅形态变异的确切遗传决定因素尚不清楚。在这里，我们探索豌豆蚜翅多态性的遗传基础，豌豆蚜可以产生有翅或无翅雄蚜。我们证实，三种类型的豌豆蚜克隆共存于自然种群中，即只产生有翅雄蚜的克隆、只产生无翅雄蚜的克隆以及产生两者混合的克隆。孟德尔遗传分析表明，豌豆蚜雄蚜的翅多态性由一个单基因座、双等位基因系统决定。利用已知位置的微卫星基因座，我们表明该基因座位于X染色体上。在一个能够进行遗传研究的系统中，翅多态性存在简单的遗传决定机制，这可能有助于对基于基因的翅形态变异的生理和分子机制进行研究。这个基因座也可用于寻找参与孤雌生殖雌蚜中描述的翅多型现象的基因，并研究多态性和多型现象之间的相互作用。
