Parkinson’s disease (PD) is a common neurodegenerative disease. Motor symptoms of rigidity, tremor, and bradykinesia and non-motor symptoms like the cognitive deficit, autonomic dysfunction, dementia, anxiety and depression all contribute to morbidity. Emerging shreds of evidence suggest the role of BDNF (Val66Met) polymorphism in PD risk and associated cognitive deficit. Hence, the current study is aimed to investigate the role of BDNF Val66Met in the risk of PD development and associated cognitive abnormalities. A total of 269 PD cases and 271 healthy, age, ethnicity and gender matched controls were recruited in the study. Genomic DNA was isolated, amplified and SNP was identified using the RFLP method and validated by Sanger’s sequencing. There was a significant association of BDNF Val66Met with PD risk in both Dominant and recessive models (GG vs GA+AA: OR: 1.47, CI: 1.04-2.09, P =0.03, GG+GA vs AA: OR: 2.32, CI: 1.07-5.00, P =0.02). The main nonmotor symptom i.e. cognitive impairment was significantly associated with the variant genotype of BDNF Val66Met Polymorphism (GG vs GA+AA: OR: 1.47, CI: 1.04-2.09, P =0.03, GG+GA vs AA: OR: 2.32, CI: 1.07-5.00, P =0.02).We found a significant association of variant genotype with disease severity, the activity of daily living as assessed by S & E score as it was found to better with wild genotype and a significant decrease in quality of life with homozygous mutant genotype. We did not find significant differences in disease duration, absolute levodopa response among the genotypes. Our results implicate BDNF Val66Met polymorphism is associated with the risk of PD, cognitive impairment, poor quality of life and greater disease severity in PD.

中文翻译：

---

脑源性神经营养因子（Val66Met）多态性与帕金森氏病风险及对临床结局的影响

帕金森氏病（PD）是一种常见的神经退行性疾病。僵硬，震颤和运动迟缓的运动症状以及认知缺陷，自主神经功能障碍，痴呆，焦虑和抑郁等非运动症状均会导致发病。越来越多的证据表明BDNF（Val66Met）多态性在PD风险和相关的认知缺陷中的作用。因此，本研究旨在研究BDNF Val66Met在PD发生和相关认知异常风险中的作用。该研究共招募了269例PD病例和271例健康，年龄，种族和性别相匹配的对照。分离，扩增基因组DNA，并使用RFLP方法鉴定SNP，并通过Sanger测序进行验证。在显性和隐性模型中BDNF Val66Met与PD风险显着相关（GG vs GA + AA：OR：1.47，CI：1.04-2.09，P = 0.03，GG + GA vs AA：OR：2.32，CI： 1.07-5.00，P ＝ 0.02）。主要的非运动性症状即认知障碍与BDNF Val66Met多态性的变异基因型显着相关（GG vs GA + AA：OR：1.47，CI：1.04-2.09，P = 0.03，GG + GA vs AA：OR：2.32，CI ：1.07-5.00，P = 0.02）。我们发现变异基因型与疾病严重程度，通过S＆E评分评估的日常生活活动之间存在显着关联，因为发现野生基因型会更好，并且质量显着下降生活与纯合突变基因型。我们没有发现基因型之间疾病持续时间，绝对左旋多巴反应的显着差异。