A link between schizophrenia and diabetes has been known for over a century, long before the use of antipsychotic medications. Type 2 diabetes mellitus is an important contributor to mortality and morbidity in this condition. Insulin growth factor 2 mRNA binding protein 2 (IGF2BP2) genetic variants rs4402960 and rs1470579 have been implicated in the etiology of type 2 diabetes mellitus in Egyptians. It is possible that both disorders share a common genetic susceptibility.Aim
The current study aimed to explore single-nucleotide polymorphism 2 (IGF2BP2) polymorphisms in a sample of Egyptian first-episode schizophrenic patients and healthy controls and to study its potential correlation with severity of psychopathology.Patients and methods
Thirty male patients with first-episode schizophrenia according to International Classification of Diseases-10 criteria and 30 healthy individuals were genotyped for IGF2BP2 rs4402960 and rs1470579 variant polymorphisms. Laboratory assessment included plasma glucose, glycated hemoglobin (HbA1c), triglycerides, total cholesterol, and high-density lipoprotein cholesterol (HDL-c). Psychological measures included Mini-International Neuropsychiatric Interview, Positive and Negative Syndrome Scale, and an Interview for the Retrospective Assessment of the Onset of Schizophrenia instrument. General Health Questionnaire was applied in healthy individuals.Results
There was a statistically significant difference between the two groups as regards 2 mRNA binding protein 2 (IGF2BP2) genetic variants rs4402960 and rs1470579 allelic frequency and distribution (P<0.05). There was a statistically significant difference between the two groups as regards the plasma/serum levels of glucose, HbA1c, total cholesterol, and HDL-c (P<0.05). There was a statistically significant positive correlation between rs4402960 variant polymorphism and plasma glucose level, HbA1c, and Positive and Negative Syndrome Scale (positive symptom scores) (P<0.05). There was a statistically significant positive correlation between rs1470579 variant polymorphism and plasma levels of glucose, HbA1c, triglycerides, and positive symptom scores (P<0.05). There was a statistically significant negative correlation between rs1470579 variant polymorphism and plasma HDL-c level (P<0.05).Conclusion
Our data support the notion that both schizophrenia and type 2 diabetes mellitus may be linked by shared genetic associates, and hence diabetes may not merely be a comorbid condition.