[Correlation between genetic polymorphisms of -855 G/C and -1140 G/A in GRIN1 gene and paranoid schizophrenia].

Objective: To investigate the single nucleotide polymorphisms (SNP) of -855 G/C and -1140 G/A in promoter regions of GRIN1 gene and find their genetic correlation to paranoid schizophrenia as well as their applicable values in forensic medicine.

Methods: The genetic polymorphisms of -855 G/C and -1140 G/A at the 5' end of GRIN1 gene were detected by PCR restriction fragment length polymorphism and PAGE in 183 healthy unrelated individuals of northern Chinese Han population and 172 patients of paranoid schizophrenia, respectively. The chi2 test was used to identify Hardy-Weinberg equilibrium of the genotype distribution. The differences of genotypes and allelic frequency distributions were compared between the two groups.

Results: Distributions of the genotypic frequencies satisfied Hardy-Weinberg equilibrium in both groups. The difference of genotypes was statistically significant between female patient group and female control group in -855 G/C distribution (P < 0.05). The differences of genotypes and allelic frequencies were statistically significant not only between the patient group and the control group but also between female patient group and female control group in -1140 G/A distribution (P < 0.05).

Conclusion: The SNP of -1140 G/A in promoter regions of GRIN1 gene might positively correlate to paranoid schizophrenia. The genetic factor of schizophrenia is involved in gender tendency. And it could be useful in forensic identification of schizophrenia.