The aim of this study was to evaluate the polymorphism in a portion of the gene regulatory region for ovarian aromatase （CYP19a） in three strains of Tilapia, Oreochomis niloticus （Linnaeus） （GIFT--Genetically Imp...The aim of this study was to evaluate the polymorphism in a portion of the gene regulatory region for ovarian aromatase （CYP19a） in three strains of Tilapia, Oreochomis niloticus （Linnaeus） （GIFT--Genetically Improved Farmed Tilapia, Chitralada and Supreme）. A total of 90 animals per strain of Tilapia, Oreochromis niloticus （Linnaeus） were analysed. After DNA extraction, samples were subjected to PCR using primers designed to flank the region of interest encompassing the sites of transcription （WT1-KTS and SRY）. Samples were analyzed by PCR-SSCP and subsequently sequenced. Three polymorphisms were identified in this region, resulting in two different sequences, in the GIFT strain while no polymorphism was found in both Supreme and Chitralada strains. At the position - 1178 the substitution of a guanine for a cytosine, at the - 1081 the exchange of guanine for adenine and at the position -1 138 we found a SNP, possible site of heterozygosity. Even with polymorphisms in the target study area, when taking the three strains into account, one can assume that the portion of the regulatory region of the ovarian aromatase gene in the Supreme strain and Chitralada does not show polymorphism.展开更多
文摘The aim of this study was to evaluate the polymorphism in a portion of the gene regulatory region for ovarian aromatase （CYP19a） in three strains of Tilapia, Oreochomis niloticus （Linnaeus） （GIFT--Genetically Improved Farmed Tilapia, Chitralada and Supreme）. A total of 90 animals per strain of Tilapia, Oreochromis niloticus （Linnaeus） were analysed. After DNA extraction, samples were subjected to PCR using primers designed to flank the region of interest encompassing the sites of transcription （WT1-KTS and SRY）. Samples were analyzed by PCR-SSCP and subsequently sequenced. Three polymorphisms were identified in this region, resulting in two different sequences, in the GIFT strain while no polymorphism was found in both Supreme and Chitralada strains. At the position - 1178 the substitution of a guanine for a cytosine, at the - 1081 the exchange of guanine for adenine and at the position -1 138 we found a SNP, possible site of heterozygosity. Even with polymorphisms in the target study area, when taking the three strains into account, one can assume that the portion of the regulatory region of the ovarian aromatase gene in the Supreme strain and Chitralada does not show polymorphism.
