Diabetes Genes

Maternally Inherited Diabetes and Deafness (MIDD)

The key features of maternally inherited diabetes and deafness (MIDD), are the presence of diabetes and/or deafness that are inherited by the children of an affected mother. 

Maternally Inherited Diabetes and Deafness (MIDD) is caused by a change or mutation in mitochondrial DNA (the most common change is known as 3243A>G) and was first identified in 1992. As all the mitochondria we inherit are inherited from our mothers the genetic change is passed down from an affected mother to all her children.  However with these particular genetic changes there is considerable variation in how much people inheriting these changes are affected.  This means some children will only have deafness or only have diabetes or may have no problems at all.   Fathers who have MIDD can be reassured that they will not pass the condition on to their children as all mitochondria are inherited from the mother. This means that although children of both sexes will inherit the affected mitochondria only women will pass the condition on to the next generation.

It is important to make a definite genetic diagnosis of MIDD as this can confirm the cause of the deafness and diabetes, aids treatment decisions, guides which additional tests are recommended and helps advise other members of the family.

MODY Request Form – use for GCK, HNF1A, HNF4A, MIDD, and other rare types of diabetes

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Scientific Information (OMIN)

Genetic Testing for MIDD