People with schizophrenia are more likely to develop type 2 diabetes than the general
population. Although an increased risk of diabetes has been attributed to
environmental determinants such as diet, lifestyle and antipsychotic drugs, the
association between these two disorders was noticed well before the advent of
current lifestyles and pharmacological interventions, raising the possibility of a
shared genetic basis. Schizophrenia and type 2 diabetes are common diseases with a
complex mode of inheritance which includes both genetic factors and environmental
determinants. As susceptibility genes for both type 2 diabetes and schizophrenia are
beginning to be identified there is increasing interest in the possibility of shared
susceptibility loci between the two conditions. This article reviews the genetic
basis to schizophrenia and type 2 diabetes and discusses the potential for shared
loci between both conditions.
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