January 26, 2003
Genetics and Heredity
Question from Palo Alto, California, USA:
My seven year old daughter, who has had diabetes for a bit more than seven years, has a fraternal twin sister, and I am constantly worried about her getting diabetes as well. Do you know what the odds are?
Answer:
Some older literature would suggest that a first degree relative (sibling, parent, child) of a patient with diabetes has about a 5% chance of developing diabetes within the next 5-10 years after the patient was diagnosed. Using screening studies (special antibody testing and/or special genetic testing), if the relative is found to have the “markers” for diabetes, the risk increases 10-fold, but that is only 50%. Unfortunately, the previous studies looking at diabetes prevention to those at risk, did not show that the preventative measures being studied worked to prevent. There are on-going studies at different approaches however. Your daughter’s diabetes team may be able to aim you to those centers, if you are interested.
For now, for practical purposes, even if you knew that your other child was “going to get” diabetes, we couldn’t stop it. So the best you can do may be to watch for the typical increased urination and thirst so that if diabetes is discovered, it is discovered early!
DS