5种体色瓯江彩鲤线粒体COII基因的序列差异和遗传标记研究

Intraspecific DNA sequence polymorphism and genetic markers in the mitochondrial COII gene from five color patterns of Oujiang color carp

利用PCR方法扩增获得瓯江彩鲤(Cyprinus carpio var.color)线粒体DNA的COII基因,测定该基因片段序列.分析了瓯江彩鲤"全红"、"粉玉"、"粉花"、"麻花"和"大花"共20只个体的序列核苷酸位点差异和遗传多态性.结果表明,"大花"和"全红"遗传多样性最为丰富,"粉花"的遗传多样性相对贫乏.在长度为604 bp的基因片段中,共检测到9个多态性核苷酸位点(占1.49%),20只个体具有4种基因型,5种体色各自的平均核苷酸位点差异分别为0.38%、0.2%、0、0.13%和0.47%.UPGMA分子系统聚类树显示,"粉花"、"麻花"和"粉玉"的遗传关系接近;"全红"相对独立成一支,与其他4种体色瓯江彩鲤的遗传关系较远.COII基因可以作为区分三分支群体的遗传标记.

The mitochondrial COⅡ gene was PCR proliferated and sequenced from 20 samples obtained from five color patterns of Oujiang color carp, designated as whole red, red with scattered black spots, whole white and white with scattered black spots. A 604 bp long partial gene segment was acquired and used to study the genetic diversity among the five color patterns. Results indicated that the COⅡ gene locus was relatively more polymorphic in the red color with large black patches （RP） and whole red （WR）, while the polymorphism in white color with large black patches （WP） was relatively poor. A total of 9 polymorphic sites and 4 haplotypes were found in the sequences of the 20 samples. The average nucleotide divergence in the five color patterns of Oujiang color carp was 0. 38%, 0.2%, 0, 0.13%, and 0.47%, respectively. The UPGMA phylogenetic tree suggested that WP, red color with small black spots （RS） and whole white （WW） were closest genetically, while WR diverged and could form another relatively independent branch. For these distinct nucleotide differences, COⅡ gene could be suitable as a genetic marker for distinguishing these three branches of different color patterns of Cyprinus carpio vat. color.