My husband was diagnosed with type 1 diabetes when he was 27, 14 years ago. At the time, they said that type 1 is hereditary and that he must have a family member with type 1. However, he only had one uncle who was diagnosed with type 2 diabetes very late in life. My husband was puzzled as to how he could have gotten the disease and put it down to the sweet tooth that he had and that he had overworked his insulin gland. Could this be right or are there other explanations?

I am concerned because I now have two children, a three-year-old girl and a five-month-old boy. I would like to know the probability of them being diagnosed with the disease especially my daughter, since I was told that girls are more likely to get it if their father has the disease. She also has a sweet tooth like my husband, although we limit the sugar she has and make sure that she follows a very healthy diet with lots of fruit and vegetables. Is this the correct way to make sure that she has the best chance of steering clear of this disease? Please, can you give me any advise that would help?

I think that either your husband got faulty information or mis-remembered. What we know about diabetes and family patterns at present is more than in the past, but still not complete. For instance, almost all people with type 1 diabetes do NOT have a family member with type 1 diabetes. If a first degree relative has type 1 diabetes, there is about a 2 to 6% chance of also developing diabetes and we know some of these genes are in the autoimmune region of the sixth chromosome. But, we do not know exactly what triggers such genes – some information about environmental chemicals and some about viruses, some about gluten/celiac. There has been negative information about immunizations as triggers in large research studies. There are some differences in mothers’ and fathers’ genetic risks for children. There is no skipping of generations.

I would suggest that you discuss these concerns with your husband’s diabetes team since they can either answer them directly or can direct you to the local pediatric diabetes team, which may be able to provide consultation and risk analysis. You can also do some research on web sites such as PubMed under general headings such as genetics of type 1 diabetes There are many excellent pediatric diabetes textbooks, including my own, Pediatric and Adolescent Diabetes, that can provide much more detailed information that might be available on inter-library loan from your local library or can be purchased from Amazon.com or any major bookstore. Also, Type 1 Diabetes in Children, Adolescents and Young Adults, Second Edition by Ragnar Hanas, M.D. has an excellent genetics chapter that is very readable and understandable.

SB