Related by context. Frequent words. (Click for all words.) 72 embryos 70 embryo 70 human embryos 68 therapeutic cloning 67 embryonic stem cells 65 embryonic cells 65 stem cells 64 cloning 63 cloned 62 reproductive cloning 62 iPS cells 60 oocytes 60 human cloning 59 stem cell 58 adult stem cells 58 Cloning 58 fertilized eggs 56 fertilized egg 56 stem cells derived 56 human embryonic stem 55 ES cells 53 ovarian tissue 53 embryonic stem cell 53 vitro fertilization 53 neural stem cells 52 vitro fertilization IVF 52 assisted reproduction 52 genetically identical 52 frozen embryos 51 IVF 51 islet cells 51 surrogate mothers 50 Embryonic stem cells 50 stem cell therapies 49 embryonic 49 Stem cells 49 adult stem cell 48 insulin producing 48 genetic defects 48 artificial insemination 47 stem cell research 47 assisted reproductive 47 fertility treatments 47 umbilical cord blood 47 ovary 47 transgenic 47 stem cell therapy 47 infertile couples 46 infertile 46 fetuses 46 artificially inseminated 46 sperm 46 transgenic mice 46 ovaries 46 organ transplants 46 Stem Cell Research 46 HFEA 46 captive breeding 45 fertility clinics 45 ova 44 progenitor cells 44 gene therapy 44 genetically modified 44 Stem cell 44 PGD 44 terminate pregnancy 44 cloned animals 44 offspring 43 genetically altered 43 bone marrow transplants 43 surrogacy 43 genetic modification 43 fetus 43 Stem Cell 43 genetically engineered 42 clone 42 Stem Cells 42 cord blood 42 genetic manipulation 42 clones 42 mutated gene 42 wombs 42 defective gene 42 umbilical cords 42 female fetuses 42 vitro 42 Advanced Cell 41 bone marrow transplantation 41 virgin birth 41 fertilization 41 prostate tumors 40 Human Fertilisation 40 malignant tumors 40 genetically 40 thymus 40 transplantation 40 unborn babies 40 abortions 40 liver transplants 40 regenerative medicine 40 ultrasounds