Parthenogenetic Stem Cells

Abstract

One of the most exciting and contentious issues in biomedical science today is the potential use of stem cells as a therapeutic intervention for a wide range of diseases with pathologies that involve cellular destruction. Stem cell therapy is currently practiced, or under active research, to repair the effects of neuromuscular degeneration, autoimmune response, ischemic attack, malignant carcinoma, congenital defects, metabolic disorders, and alcohol-related pathologies. When stimulated in a proliferative environment, stem cells may also provide the raw material for large-scale ex vivo tissue regeneration. There are several sources of human stem cells for laboratory culture, but the primary source of pluripotent human embryonic stem cells is the inner cell mass of in vitro fertilized embryos. Despite the potential rewards to medicine, experimentation using cells from viable human fetuses has triggered global political and ethical controversy that has slowed down the pace of research. An alternative source of human embryonic stem cells that circumvents some of these issues would significantly enhance research in this area. Parthenogenetically derived stem cells may represent such a resource. Parthenogenesis involves activation of the oocyte without sperm, and produces a nonviable blastocyst. That is, the activated egg develops to the blastocyst (and so can be used to generate stem cells), but it will not produce a viable pregnancy in mammals. The unique genesis of the embryo, and its arrested development at blastocyst, may afford sufficient moral and political latitude to enable its acceptance as an experimental entity. Research is ongoing to assess the genetic and phenotypic similarity of parthenogenetic stem cells (PSCs) to other stem cell types from mammalian models and to human stem cells derived from fertilized embryos. Keywords: Chimera; Genomic Imprinting; Parthenogenesis; Parthenote; Teratoma; Uniparental Disomy