cloning, stem cells and genome editing Flashcards
are identical twins clones
yes
what is cloning
Creating a genetically identical copy
dolly the sheep
- Not the first clone, but the first to becloned from an adult cell, rather than an embryo
- Somatic cell nuclear transfer (SCNT)
- 1996: Roslin Institute, University of Edinburgh
- Ian Wilmut
benefits to cloning
- Human genes inserted into sheep/cattle that
then cloned produce therapeutic agents in milk - Research where genetic background important
- Producing multiple copies of prized stock
disadvantage to cloning
extremely inefficient
concerns with premature aging
Doesn’t resolve lack of genetic diversity
Concerns around premature aging with cloning, why
Shortened telomeres in some clones
how can we use cloning to save endangered species
- Nuclear material from species to be cloned
- Donor egg from related species
why would cloning be used to save endangered species
- Too few reproductively capable animals left
- Can’t, or won’t, mate
3 general classes of stem cells
- Embryonic Stem Cells
- Adult Stem Cells
- Induced Pluripotent Stem Cells
embryonic stem cells
- From the inner cell mass of the blastocyst
- Inner cell mass gives rise to the embryo
- Cells are pluripotent
adult stem cells
- Mesenchymal Stem Cells
- Majority of tissues
- Tissue maintenance & repair
- Restricted differentiation potential
- multipotent
are adult stem cells multipotent or pluripotent
multipotent
are embryonic stem cells multipotent or pluripotent
pluripotent
induced pluripotent stem cells
- Generated from differentiated cells
- Skin fibroblasts: adult, juvenile
- ‘Reprogrammed’
- Pluripotent state
- Very similar to ESCs, but without the need to harvest embryos
how are induced pluripotent stem cells different to embryonic stem cells
Very similar to ESCs, but without the need to harvest embryos