Science - Cloning
- A clone is an organism that was made by exactly copying the genetic sequence of another organism. Cloning occurs in nature. Examples of natural cloning include mitosis and banana plants.
- Types of cloning:
- Nuclear Transfer Cloning:
- Somatic: any cell that is not a sperm or egg.
- The nucleus of one somatic cell and egg cell is taken out and the somatic cell’s nucleus is implanted into the egg’s empty space where its nucleus used to be
- Eventually the egg begins to divide (this does not always happen, and is why Nuclear Transfer Cloning is not very efficient), and becomes a full organism
- Therapeutic Cloning: An embryo is cloned in the normal way, but instead of letting it develop into a fetus/organism, it’s interrupted at the blastocyst stage (when it’s still just a ball of cells) and used to repair cellular damage to a patient.
- This is useful because the cells in a blastocyst are “stem cells”: they have not yet differentiated, so they can become any kind of tissue needed.
Dolly the Sheep
Dolly the Sheep was the first ever mammal to be cloned
- 1/400 attempts successful
- around 300 embryos used
- Dolly died at 6 years old (most sheep die at around 12) due to a lung disease, NOT cloning
- First step towards human cloning
- Cloning the best cattle for meat and milk production
- Embryonic stem cells for medical use
- Clones as “spare parts” for humans
- Negatively affected stem cell research by association
- Cloning research moved to countries with less restrictions (Such as China and Japan)