Genetic Engineering and Medicine

This is the process of taking genes from one organism and placing them in another. Ethical arguments aside, this can have great advantages to medical science when genes from humans are put into bacteria.

Growth Hormone is, not surprisingly, a major factor in human growth – a deficiency in this hormone (normally produced by the tiny pituitary gland in the brain) can lead to drastically stunted growth. Several decades ago the only treatment was Growth Hormone extracted from the pituitary glands of corpses. To many this may seem barbaric – it was certainly unsafe, as at least a couple of cases of nCJD (the human variant of ‘mad cow disease’) have been traced back to this cause.

The answer to the problem was found in bacteria that had been altered to carry a human gene – the gene for human Growth Factor. When the gene is placed correctly in the bacteria (not an easy task) it, and all its descendents will make Growth Factor that is identical to that made by a human – bacteria grow very fast and can make Growth Factor very quickly under the correct conditions. This means that this hormone is available, risk free, to all who may need it.

Insulin, as many people will know is a vital treatment for diabetics. In non-diabetics the hormone is made in special cells in the pancreas and its release decreases blood glucose levels (a different hormone – glucagon – does the opposite). If the body does not make insulin then the blood-sugar level rises to a very high level with coma and death following.

Before the advent of genetic engineering, diabetics used insulin obtained from cows – now the insulin gene can be put into bacteria and they can make ‘real human’ insulin. This process is also cheaper.

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