Diabetes and genetics

Type 1 diabetes: Most commonly you will have to inherit risk factors for diabetes from both of your parents. If both of your parents have diabetes, you have a 30% increased risk of developing it too, whereas if only on of them has it, you have a 2-8% risk. But not everyone at risk will get diabetes and so research is needed to establish the environmental factors, to find out what triggers diabetes in some people, and what makes it stay dormant in others.
A suspected trigger is cold weather, since diabetes 1 tends to be developed in the winter months rather than during the summer. Also certain viruses could be a potential trigger for predisposed diabetics.

Type 2 diabetes: For reasons unknown, type 2 diabetes has stronger familial bonds. If both of your parents have type 2 diabetes, you are at a 75% increased risk of developing it too. If only one of them have it, you are at a 15% risk.
What is important to remember, is that genes alone do not carry the responsibility for developing type 2 diabetes. Your lifestyle and environment plays a bigger role than in type 1 diabetes. Usually poor diet and exercise habits “run in the family”, so if (either of) your parents have type 2 diabetes and your family also has an unhealthy lifestyle, it is not necessarily the predisposition that is the cause of your diabetes. It is likely due to your lifestyle choices.