Diabetes and schizophrenia gene link search continues
MedWire News: The search for a genetic basis in the association between diabetes and schizophrenia continues after UK scientists found no evidence to link the peroxisome proliferator-activated receptor gene (PPARG) to schizophrenia.
Schizophrenia patients have a four-fold increased risk for Type 2 diabetes compared with the general population. Both conditions are highly heritable, and studies have revealed dozens of genes associated with Type 2 diabetes.
To investigate further, Jun Wei, from the University of the Highlands and Islands in Inverness, and colleagues genotyped 221 British nuclear families with fathers, mothers, and affected offspring with schizophrenia for eight single nucleotide polymorphisms (SNPs) in PPARG, one SNP in the phospholipase A2 group 4 homolog A gene (PLA2G4A), and one SNP in the cyclooxygenase 2 gene (PTGS2).
One family had two affected offspring, giving a total of 222 patients with an average age of 30.5 years, 148 fathers and 204 mothers, the team reports in the journal Prostaglandins, Leukotrienes, and Essential Fatty Acids.
None of the eight PPARG SNPs demonstrated allelic association with schizophrenia. There was a weak association of marginal significance between schizophrenia and the rs2745557 and rs10798059 SNPs in the PTGS2 and PLA2G4A loci, respectively.
Further analysis on the gene–gene interaction test did not reveal any evidence of either the cis-phase interaction for the PLA2G4A and PTGS2 combinations, or the trans-phase interaction for the PLA2G4A and PPARG combinations.
“Thus, we don’t have any evidence to suggest that abnormal metabolisms of membrane phospholipids interact with PPARG, which may have explained the high prevalence of Type 2 diabetes in schizophrenia,” the researchers write.
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By Liam Davenport