Lu CuiYun

Identification of significant correlation microsatellite markers with eye diameter and eye cross of mirror carp,Cyprinus carpio L.

Marker-assisted selection is commonly used to find molecular markers or genes associated with eco-nomic traits that are often controlled by multiple genes and inherited as quantitative traits.Eye diameter(ED) and eye cross(EC) are two of the most important quantitative traits in common carp.They are also important mor-phological characteristics often used in fish taxonomy.We used a full-sib family(68 individuals) of hybrid mirror carp(Cyprinus carpio L.) to analyze the correlation between 164 microsatellite markers,obtained from a bacterial artificial chromosome(BAC),with ED and EC.We obtained 401 alleles and 463 genotypes from the 164 markers.We used a general liner model with permutation test(10 000 times) to evaluate the relationship between the geno-types and the two traits.Twenty-two of the SSR markers had significant correlation with ED and/or EC(P0.05).Six SSR markers,including CAFS1526,were significantly correlated with ED(P0.05) and 11 SSR markers,in-cluding CAFS0882,were significantly correlated with EC(P0.05).Five SSR markers,including CAFS1298,had significant correlation with both ED and EC(P0.05),and CAFS1298 and CAFS1423 were highly significantly correlated with both ED and EC(P0.01).The genotypes at each marker related to the two traits were obtained using Duncans multiple comparison test.The markers significantly related to ED and EC were assigned to a linkage map,and nine markers were consistent with the QTL mapping for ED or EC,which explained 13.3–20.9% of the phenotypic variance.These functional markers from the BAC and its genotypes may be used for both MAS and constructing an integrated linkage map with a physical map of the common carp.

Rates and patterns of microsatellite mutations in common carp (Cyprinus carpio L.)

During genotyping 150 microsatellites in a F1 family of common carp, six mutations were found at five microsatellite loci. The overall mutation rate of common carp microsatellites was 2.53 X 10(-4) per locus per generation. At five loci, mutations increased the length of alleles by at least one repeat unit, suggesting mutations at microsatellite loci in common carp do not follow strict stepwise mutation model. The data on mutation rates and patterns can facilitate population genetics studies, and provide useful parameters for estimating a long-term effective population size of common carp.