Embryonic stem-cell gametes: the new frontier in human reproduction.

As infertility increases and gamete donations decline, an alternate source of sex cells may prove valuable for research and infertility treatment. This article examines the social and scientific value of gametes derived from the differentiation of established human embryonic stem (ES)-cell lines (ES-cell-derived gametes) and customized gametes created using nuclear transfer technologies to contain a haploid set of genes creating children genetically related to parent(s). ES-cell-derived gametes may be valuable as a resource for biomedical research, instruction and training in assisted reproductive technologies and perhaps for creating children. The creation of children by ES-cell-derived and customized gametes may not result in psychological harm to children but customized gametes may lead to physical harm to children or an accumulation of gene mutations in a population. Although the creation of new types of children using ES-cell gametes provides more reproductive choices to both fertile and infertile individuals, the risk or physical harm to children from customized gametes may be so severe that the scope of reproductive liberty must be limited. Further scientific and ethical analysis of the creation of children by ES-cell gametes is required.