GM
Hi!
Genetic modification means changing the DNA (which contains instructions for growth and function) of an organism by altering or adding a gene (genes are made from DNA). Scientists have learnt how to insert a gene from one kind of life into another, for example from an animal to a plant, unlike traditional plant breeding. This is done to give a plant a quality it might not otherwise have had - for example, toxicity to a pest, increased yields, medicinal properties, drought resistance, salt tolerance, and frost-resistance from a fish anti-freeze gene.
There are risks to this technology. It often mixes genes from species that could not possibly breed naturally, so the results are unknown. It encourages the use of pesticides (the GM crops are bred to be resistant to them) and fertilisers, which cause pollution due to runoff, and may harm the local wildlife and the soil. Farmers become dependent on agribusiness for the fertilisers and for the seed, which is patented and may have infertility built into it. The wind carries any viable pollen to nearby farms and wild areas where it may interbreed.
GM crops have mostly become popular because of the increased yields. Much of it is grown in the USA, whereas many other countries have been far more cautious. There have been trials in the UK, where foods containing GM ingredients are labelled so that consumers can choose whether or not to have them. Some supermarkets do not carry them or limit their product ranges.