  The foregoing has focused on the ethics of creating chimeras, but much of the ethics discussion has either attempted to infer public policy conclusions straightaway or has taken place within discussions about what public policy should be. The recommendations of the National Academies guidelines prohibit the introduction of hESCs into nonhuman primate blastocysts (NAS 2006, 41), citing concerns about the potential human contribution of such cells. The International Society for Stem Cell Research guidelines prohibit research that involves introduction embryos into which hESCs have been introduced into any human or nonhuman primate uterus (ISSCR 2006). Although the ISSCR guidelines do not provide a rationale for this prohibition, the only potentially relevant rationale articulated in the accompanying commentary cites a concern for the creation of “humanized cognition, awareness, or other mental attributes” (Hyun et al. 2007, 162). Both groups appear to intend their recommendation to apply to all institutions carrying out hESC research, including public institutions. President Obama’s National Institutes of Health regulations prohibit federal funds for research in which hESCs are introduced into nonhuman primate blastocysts (National Institutes of Health 2009). And, of course, proponents of stem cell research typically do not argue only that the research is permissible but also that the research should be eligible for federal funding.