September 5, 2003
Diagnosis and Symptoms, Genetics and Heredity
Question from :
My eight year old son was diagnosed with type 1 diabetes within a week of his sixth birthday, and I have carefully researched my (and my husband’s) family tree for anyone else who might possibly have this disease, but I can find no one! I have searched for individuals who may have exhibited/died from symptoms like diabetes and can find no one (all have died from cancer). I have one great uncle who was extremely overweight and developed type 2 diabetes very late in life. My husband has several aunts who have type 2 diabetes (all developed during their 50s or later).
According to my child book entitled “Caring for Your Baby and Young Child” (from the American Academy of Pediatrics), type 1 diabetes is inherited and special genes must be present on both sides of the family in order for it to develop. I can find no other research on this matter. I am concerned because I am considering a second child, but I feel that my husband and I are genetically liable for what happened to our son, and we do not wish this disease to be passed on to another child. Is there any information/research on this subject?
Answer:
Type 1A (autoimmune) diabetes is indeed genetically determined, but it has been shown that other environmental factors are required to trigger insulin dependence. These latter are poorly identified: early introduction of cow’s milk was a popular theme for many years, but that has finally been discounted. At all events, it is actually unusual to find an immediate family history at the time of onset.
If you wish to have another child the risks of this kind of diabetes are about 1:20, a figure that could be fine-tuned if both you and your husband would be willing to get HLA antigen typing, but this is a modestly expensive procedure. There have of course been an immense number of studies on this theme.
DOB
