玉斑锦蛇染色体研究

The chromosome study of Elaphe mandarina

目的通过研究玉斑锦蛇Elaphe mandarina的染色体核型和带型,为探讨锦蛇属的分类和亲缘关系提供重要的证据。方法以产于贵州的玉斑锦蛇Elaphe mandarina为研究材料,应用染色体的核型、C带、银带分析技术。结果玉斑锦蛇的核型为2n=38,含有20个大型染色体和18个小型染色体;每条大型染色体两端均具端粒区C带;第1,2,5,7号染色体具着丝粒区C带;第4号和第5号染色体中的一条同源染色体C带浓染,几乎占据整条染色体;标准NORs位于第11号染色体。结论玉斑锦蛇是迄今已报道的锦蛇属中染色体数目最多、端粒区C带最多的物种;锦蛇属的标准NORs具有属的银染特征。

Aim To describe chromosomes of the Elaphe mandarina from Guizhou.Karyotype has 38 chromosomes,with 20 macrochromosomes and 18 microchromosomes.Methods All of the macro-chromosomes possess telomeric C-band at every end of the chromosomes.Results No.1,2,5 and 7 each possesses a centromeric C-band.The C-banding positive blocks of No.4 and one homologue of No.5 are rather largely occupying almost whole chromosomes.Standard NORs are located on No.11 chromosome.Conclusion The species possesses the highest number of chromosomes and highest number of telocentric chromosomes among the species of genus Elaphe examined.The variations of chromosome number and C-bands among the species of the genus Elaphe were discussed,the standard NORs are located on the largest micro-chromosome which might be the character of the genus Elaphe.