RNAi-mediated knockdown of p66Shc reduces embryo failure and increases blastocyst development.

<p>Groups of embryos were either: non-injected, injected with negative control siRNA molecules or injected with the p66Shc-specific siRNA molecules RNAi-A or RNAi-E. The frequency distribution of embryo development was assessed on the 8th day of <i>in vitro</i> culture. Different letters above the histogram bars represent significant differences (P<0.05) in developmental frequencies between groups. The proportion of 2–4 cell embryos was increased by the negative control siRNA while both p66Shc specific siRNA molecules produced significant decreases in embryo arrest. The distribution of 5–8 cell embryos was unaffected by any treatment. The proportion of 9–16 cell embryos was significantly decreased in both p66Shc-specific siRNA groups. Negative siRNA injection significantly decreased the proportion of blastocyst stage embryos. The proportion of both morula and blastocyst stage embryos was increased by both of the anti-p66Shc siRNA molecules.