生物性别决定的复杂性

摘要

动物和植物的性别决定方式复杂多样，细菌的性别决定则比较简单。人类的性别决定方式为XX-XY型性别决定方式，Y染色体在人类男性的性别决定和发育中起决定作用，Y染色体上的基因启动了和性别决定有关基因的差异表达，进而启动了个体的性别发育过程。果蝇的性别决定最终取决于X染色体的数目和常染色体套数的比值（X/A）。高等植物多为雌雄同株，无明显的性染色体决定性别机制。细菌的性别由细菌是否含有致育因子即F因子而决定，含有F因子的菌株相当于雄性，不含F因子的菌株相当于雌性。总体来说，遗传组成是生物性别决定的物质基础，但环境因素对性别决定也有影响。主要阐述了生物界主要的性别决定方式及环境因素对性别决定的影响，综述了人类和果蝇性别决定的分子基础的研究进展。%There are many kinds of sex determination patterns in both animals and plants, but the sex determination for bacteria is rather simple. The sex development of the human individuals is determined by the chromosomal difference, chromosome Y initiates differential expressions of the sex-related genes and plays an important role in the sex determination. For drosophila, the ratio of X/A determines the sex development. Many kinds of the plants are hermaphrodites and do not have specific sex determination patterns. The sex determination for bacteria follows a rather simple way, the F facter bearing bacterium strains are male bacteria, otherwise, the bacterium strains without F factor are female ones. Generally, the genetic constitution, or the chromosome difference usually determines the sex developmental possibility of the organisms, but the environmental factors can control maleness or femaleness of organisms in some kinds of species. In this paper, the different patterns of varieties of sex determinations, their possible molecular mechanisms and the influencing role of environmental factors are reviewed.