What is diabetes?
Diabetes affects over 2.6 million people in the UK. People with diabetes cannot control the level of sugar in their blood. There are two main types of diabetes. The symptoms of Type 1 diabetes usually first appear in childhood, and can only be treated with regular injections of insulin. Type 2 diabetes usually only affects people over the age of 40, and can be treated by changing their diet. In later life, the condition may cause eye, nerve, kidney or heart problems.
What causes diabetes?
A protein hormone called insulin normally controls the levels of sugar in your blood. After a meal, your blood sugar level rises and insulin is released from your pancreas into your blood. This helps your body's cells to remove sugar from the blood and use it for energy. In Type 1 diabetes, the cells in the pancreas that make insulin are gradually destroyed by the body's own immune system. In Type 2 diabetes, either the pancreas does not make enough insulin or the body becomes resistant to its effects.
How many genes have been associated with diabetes?
Type 1 and Type 2 diabetes both run in some families. Research shows that people with Type 1 diabetes often have certain gene variants. But genes cannot be the whole story, as studies of identical twins indicate. If one twin has Type 1 diabetes, the other (who has identical genes) is affected only one-third of the time. Type 2 diabetes involves many different altered genes, around 25 have been identified so far, but there are likely to be more.