Nile tilapia (Oreochromis niloticus) gene expression profiling in males and females at early embryonic development (2, 5 and 9 days post fertilization ). Oreochromis niloticus

Commercial production of tilapia relies on monosex cultures of males, which so far proved difficult to maintain in large scale production facilities. Thus, a better understanding of the genetic architecture of the complex trait of sex determination in tilapia is needed.We aimed to detect genes that were differentially expressed by gender at early embryonic development. Artificial fertilization of O. niloticus females with either sex-reversed males (ΔXX) or genetically-modified YY 'supermales' resulted in all-female and all-male embryos, respectively. Pools of all-female and all-male embryos at 2, 5 and 9 days post fertilization were used for custom Agilent eArray. Overall design: 56 pool samples of Nile tilapia full siblings groups (female or male) at day 2, 5 or 9 post fertilization were subjected to total RNA extraction from whole embryo tissues and hybridized to the custom Agilent array. Each sample was yielded from different cross of artificial fertilization: six dams X five sires. The resulting gender were known based on the sire, sex-reversed males (ΔXX) or genetically-modified YY 'supermales' resulted in all-female and all-male embryos, respectively.