GCH1 variants contribute to the risk and earlier age-at-onset of Parkinson's disease: a two-cohort case-control study.

Abstract

BACKGROUND:

Common and rare variants of guanosine triphosphate cyclohydrolase 1 (GCH1) gene may play important roles in Parkinson's disease (PD). However, there is a lack of comprehensive analysis of GCH1 genotypes, especially in non-coding regions. The aim of this study was to explore the genetic characteristics of GCH1, including rare and common variants in coding and non-coding regions, in a large population of PD patients in Chinese mainland, as well as the phenotypic characteristics of GCH1 variant carriers.

METHODS:

In the first cohort of this case-control study, we performed whole-exome sequencing in 1555 patients with early-onset or familial PD and 2234 healthy controls; then in the second cohort, whole-genome sequencing was performed in sporadic late-onset PD samples (1962 patients), as well as 1279 controls. Variants at target GCH1 regions were extracted, and then genetic and detailed phenotypic data were analyzed using regression models and the sequence kernel association test. We also performed a meta-analysis to correlate deleterious GCH1 variants with age at onset (AAO) in PD patients.

RESULTS:

For coding variants, we identified a significant burden of GCH1 deleterious variants in early-onset or familial PD cases compared to controls (1.2% vs 0.1%, P < 0.0001). In the analysis of possible regulatory variants in GCH1 non-coding regions, rs12323905 (P = 0.001, odds ratio = 1.19, 95%CI 1.07-1.32) was significantly associated with PD, and variant sets in untranslated regions and intron regions, GCH1 brain-specific expression quantitative trait loci, and two possible promoter/enhancer (GH14J054857 and GH14J054880) were suggestively associated with PD. Genotype-phenotype correlation analysis revealed that the carriers of GCH1 deleterious variants manifested younger AAO (P < 0.0001), and had milder motor symptoms, milder fatigue symptoms and more autonomic nervous dysfunctions. Meta-analysis of six studies demonstrated 6.4-year earlier onset in GCH1 deleterious variant carriers (P = 0.0009).

CONCLUSIONS:

The results highlight the importance of deleterious variants and non-coding variants of GCH1 in PD in Chinese mainland and suggest that GCH1 mutation can influence the PD phenotype, which may help design experimental studies to elucidate the mechanisms of GCH1 in the pathogenesis of PD.

• Authors: Hong-Xu Pan, Yu-Wen Zhao, Jun-Pu Mei, Zheng-Huan Fang, Yige Wang, Xun Zhou, Yang-Jie Zhou, Rui Zhang, Kai-Lin Zhang, Li Jiang, Qian Zeng, Yan He, Zheng Wang, Zhen-Hua Liu, Qian Xu, Qi-Ying Sun, Yang Yang, Ya-Cen Hu, Ya-Se Chen, Juan Du, Li-Fang Lei, Hai-Nan Zhang, Chun-Yu Wang, Xin-Xiang Yan, Lu Shen, Hong Jiang, Jie-Qiong Tan, Jin-Chen Li, Bei-Sha Tang, Ji-Feng Guo
• Journal: Translational neurodegeneration (Transl Neurodegener) Vol. 9 Issue 1 Pg. 31 (08 04 2020) ISSN: 2047-9158 [Print] England
• PMID: 32746945 (Publication Type: Journal Article, Research Support, Non-U.S. Gov't)

Chemical References

• GCH1 protein, human
• GTP Cyclohydrolase

Topics

• Adult
• Age of Onset
• Aged
• Case-Control Studies
• Cohort Studies
• Female
• GTP Cyclohydrolase (genetics)
• Genetic Predisposition to Disease (epidemiology, genetics)
• Genetic Variation (genetics)
• Humans
• Male
• Middle Aged
• Parkinson Disease (epidemiology, genetics)