基于Cytb和ITS1基因的两种不同体型湘华鲮遗传差异研究

GENETIC DIFFERENCES OF TWO DIFFERENT SOMATOTYPES SINILABEO DECORUS TUNGTING(NICHOLS)BASED ON CYTB AND ITS1 GENE

研究采用Cytb和ITS1基因序列作为分子标记对平背型和高背型湘华鲮的遗传差异进行分析。研究结果表明,基于Cytb与ITS1基因序列,高背型和平背型湘华鲮在碱基组成上均表现出偏向性,且呈现出高单倍型多样性和低核苷酸多样性的特征。遗传距离分析和NJ系统树构建的结果表明,两种不同体型湘华鲮遗传分化程度低,未达到种群分化的水平。综上所述,高背型和平背型属于同一个种群。研究结果丰富了湘华鲮分子生物学数据,为湘华鲮种质资源保护及产业发展提供了理论依据。

Sinilabeo decorus tungting(Nichols)is a wild endemic fish in Hunan Province,however,due to overfishing and environmental damage,the germplasm resources of wild S.decorus tungting are scarce.In order to effectively protect germplasm resources of S.decorus tungting,artificial breeding research has been carried out.In the process of domestication and parental cultivation,it was found that there were two somatotypes in the wild population:the high-back type and the flatback type.The countable traits analysis showed that there was no significant difference between the two different somatotypes S.decorus tungting on fin formula and scales.To explore the genetic differences between the two somatotypes of S.decorus tungting,Cytb and ITS1 gene sequences were used as molecular markers to analyze the genetic differences.The results showed that based on the Cytb and ITS1 gene sequences,both the high-back type and the flatback type were showed a bias in base composition.And two somatotypes of S.decorus tungting were showed high haplotype diversity and low nucleotide diversity.In addition,the results of genetic distance analysis and NJ tree construction showed that the degree of genetic differentiation of the two somatotypes was low,which did not reach the level of population differentiation.In conclusion,the high-back type and flatback type belongs to the same population.The results of this study enriched the molecular biological data of S.decorus tungting,and provided theoretical basis for the protection and industrial development of S.decorus tungting germplasm resources.The reasons for the formation of the high back type of S.decorus Tungting was unknown and needs further study.