Cloning describes the process of producing genetically identical copies of a biological entity. The genetic copy is thus called a clone. A relatively new field of scientific endeavour, cloning offers up an array of potential benefits but also poses a correspondingly high number of ethical questions, especially concerning the potential for human cloning.
Artificial cloning
Artificial cloning – as opposed to naturally occurring processes of cloning as displayed, for instance, by some plants and single-celled organisms, as well as in identical twins – is typically divided into three main branches:
• Gene cloning, which reproduces specific genes or segments of DNA.
• Reproductive cloning, which produces animals that are perfect copies of their antecedents.
• Therapeutic cloning, which creates embryonic stem cells, usually with the aim of producing living tissues that can replace diseased or injured tissues.
Gene research is generally considered the least controversial strand, typically involving isolating and inserting a specific gene into a third-party carrier (a vector) – for instance, bacteria or viruses – where it is then encouraged to grow. The resulting cloned genes can then be used for research and experimentation.
Reproductive cloning, by contrast, creates a whole new, distinct life form by removing mature, somatic cells (cells from the body such as skin cells) from the animal to be cloned, extracting DNA from it and inserting it into an egg cell that has had its nucleus (in which its own DNA resides) removed. After an initial period of development in the laboratory, the egg is then implanted into an adult female who will birth the clone. For now, there has been no proven instance of successful human cloning.
Animal cloning has both potential medical and agricultural implications. For example, animals may be genetically modified to produce particular proteins for use in medical treatments, or may be used in medical experimentation (freeing researchers of having to process the impact of countless ‘variables’ inherent in non-cloned subjects). Agriculturally, it becomes possible to breed animals with, for example, high milk yields or particularly good meat – although as yet the costs ensure that cloned animal products in the local supermarket remain some way off.
In therapeutic cloning, an embryo is cloned for the single intention of harvesting stem cells – a simple cell that may develop into any one of various kinds of other cells – for the purpose of medical experimentation and, in theory, the production of replacement tissues. Whereas reproductive cloning raises ethical questions by creating entities that exactly physiologically mimic a naturally occurring life – with attendant implications for issues of identity, autonomy, dignity, and social and religious custom – therapeutic cloning challenges us because it demands the destruction of embryos in their earliest stages of development. Not to mention the potential dangers of passing on ‘faulty’ or unfavourable genes through the generations.
Such moral quandaries remain essentially unanswered despite rapid technological progress and the needle of our collective moral compass continues to spin in uncertain directions.