Abstract: Objective To evaluate the relationship between the tyrosine hydroxylase(TH) gene and mental disorder by comparing the two TH gene SNP points(extron 3 and intron 9) of patients with mental disorders and normal human. Methods DNA extracted from specimens of patients and normal subjects were quantified by using Real-time PCR. Results (1) G334A distribution was: G=0.133,A=0.867 in patients with schizophrenia,G=0.116,A=0.884 in patients with depression,and G=0.214,A=0.786 in normal group. (2) C5162G distribution was: C=0.962,G=0.038 in patients with schizophrenia,C=0.959,G=0.041 in patients with depression,and C=0.961,G=0.039 in normal group. Conclusion There are statistically significant differences in G334A locus between normal people and patients with mental disorders,but no statistically significant differences in C5162G locus.

Key words: forensic genetics, tyrosine hydroxylase, polymorphism, single nucleotide, psychotic disorders