Study On The Heterosis And Differences Of Gene Expression In Anas Platyrhncos Var Domestica, Cairina Moschata L And Their Crossbreds

In order to reveal form factors and molecular genetic basis of heterosis,in the research,mRNA differential display was used to analyze the differential gene expression of liver,chest musle,ovary,hypophsis and epiphsis five tissues between crossbred and its parents,which were Cairina moschata L(FF) and Anas platyrhncos var domestica(BB).The results showed that there were significant differences of gene expression between crossbred and their purebreds.Total of 180 differential displayed cDNA bands were found from nearly 542 reproducible bands with 5 pairs of primers,which shows the differences of gene expression between hybrids and its parents were very obvious in quantity and quality. Seven types of differential expression patterns were found:Co-dominance expressed pattern (Ⅰ),Underexpression of parental fragements in hybrids(Ⅱ),Over-expression of parental fragements in hybrids(Ⅲ),Hybrid-absence expressed pattern(Ⅳ),Single parent-specific expressed pattern(Ⅴ),Dominant expression fragements of single parent in hybrids(Ⅵ), Hybrid-specific expressed pattern(Ⅶ).Correlation analysis indicated that there were correlation between the pattern ofⅥand the heterosis percentage of average body weight and daily increasing weight at 10 weeks (P＜0.05),while there are negative correlation between the pattern ofⅡand the heterosis percentage of average body weight and daily increasing weight at 10 weeks(P＜0.05).And there were significant correlation between the pattern ofⅢand the heterosis percentage of lean meat rate(P＜0.01),while there are significant negative correlation between the pattern ofⅡand the heterosis percentage of lean meat rate(P＜0.01).But there are not any correlation between 7 patterns and the heterosis percentage of feed reward(P＞0.05).7 differential expressed sequences confirmed were sequenced,one had high similarity with obese gene of chicken(e=0);Other 6 sequences,without homologous sequences by BLAST analysis,maybe were new EST sequences.The sequence of differentially expressed ob had high similarity with chicken tissue,product of which can remarkably cut down the amounts of fat mass.The differential expression of obese gene between hybrid(FB) and its purebreds was likely to the heterosis of lean meat rate of hybrid.These results showed the heterosis of production traits were related to gene differential expression between duck hybrid and their parents.