Association between gene polymorphism and depression in Parkinson's disease: A case-control study.
OBJECTIVE
To investigate possible associations of Parkinson's disease (PD) with polymorphism in depression-related genes and in the alpha-synuclein (SNCA) gene.


METHODS
A consecutive series of patients with PD were divided into those with depression and those without it. Patients (330) were genotyped at four single-nucleotide polymorphisms (SNPs) in four genes previously associated with depression, as well as four SNPs in the PD-associated SNCA gene.


RESULTS
Of 330 patients, 125 (37.9%) had depression and 205 (62.1%) did not. Univariate analysis revealed significant differences between the two groups in minor allele frequency at the SNP rs1545843 in the SLC6A15 gene (p<0.05), as well as in frequencies of genotypes and minor alleles at rs78162420 in the TPH2 gene (all p<0.05). Logistic regression identified the following risk factors for depression among patients with PD: Hoehn and Yahr stage>2 (OR 1.759, 95%CI 1.035-2.989, p=0.037), AA genotype at rs1545843 (OR 1.866, 95%CI 1.017-3.426, p=0.044), and AC genotype at rs78162420 (OR 5.036, 95%CI 1.451-17.484, p=0.011).


CONCLUSIONS
Among patients with PD, depression is associated with polymorphism at rs78162420 and rs1545843, both previously linked with depression. Our results may help clarify the pathogenesis of depression in PD.
Department of Neurology, West China Hospital, Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan Province 610041, PR China.
Jinhua
J
Zheng
Department of Neurology, West China Hospital, Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan Province 610041, PR China.
Xinglong
X
Yang
Department of Neurology, West China Hospital, Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan Province 610041, PR China.
Quanzhen
Q
Zhao
Department of Neurology, West China Hospital, Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan Province 610041, PR China.
Sijia
S
Tian
Department of Neurology, West China Hospital, Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan Province 610041, PR China.
Hongyan
H
Huang
Department of Neurology, West China Hospital, Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan Province 610041, PR China.
Yalan
Y
Chen
Department of Neurology, West China Hospital, Sichuan University, 37 Guo Xue Xiang, Chengdu, Sichuan Province 610041, PR China. Electronic address: neuroxym999@163.com.
Yanming
Y
Xu
D000368:Aged; D026921:Amino Acid Transport Systems, Neutral / Q000235:genetics*; D044466:Asian People; D050976:Basic-Leucine Zipper Transcription Factors / Q000235:genetics; D016022:Case-Control Studies; D003863:Depression / Q000209:etiology / Q000235:genetics*; D005260:Female; D005787:Gene Frequency; D056726:Genetic Association Studies; D020022:Genetic Predisposition to Disease / Q000235:genetics*; D005838:Genotype; D006801:Humans; D016015:Logistic Models; D008297:Male; D008875:Middle Aged; D009419:Nerve Tissue Proteins / Q000235:genetics*; D010300:Parkinson Disease / Q000150:complications / Q000235:genetics*; D020641:Polymorphism, Single Nucleotide / Q000235:genetics*; D014365:Tryptophan Hydroxylase / Q000235:genetics*; D051844:alpha-Synuclein / Q000235:genetics
D026921:Amino Acid Transport Systems, Neutral; D050976:Basic-Leucine Zipper Transcription Factors; D009419:Nerve Tissue Proteins; C506212:SLC6A15 protein, human; C489490:TEF protein, human; D051844:alpha-Synuclein; C494784:TPH2 protein, human; D014365:Tryptophan Hydroxylase
Association studies in genetics; Depression; Parkinson's disease; rs1545843; rs78162420