| Objective:Parkinson’s disease(PD)is the most common cause of motor impairment in the elderly.It is the second most common neurodegenerative disease in clinical practice after Alzheimer’s disease.In addition to abnormal aggregation and transformation ofα-synuclein leading to PD,a microtubule-associated protein tau based pathogenesis of disease has also been proposed in PD.Although the possible role of Tau gene in the pathogenesis of Parkinson’s disease remains unclear,in vitro studies suggest thatα-synuclein may interact with Tau protein by regulating Tau phosphorylation.De-function or deposition of Tau protein may accelerate the degeneration of dopaminergic neurons.Earlier studies reported dinucleotide repeat polymorphisms in intron 9,and later more attention was paid to the common haplotype H1 of 4--8 common polymorphisms throughout the Tau gene.The MAPT gene,which encodes the microtubule-associated protein tau,is located on chromosome 17.The main haplotypes of MAPT are H1 and H2,respectively.They are mainly formed by the 900kb inversion of Q21region on chromosome 17 and the 238bp deletion of intron 9 in H2.Abnormal proteins expressed by different haplotypes may lead to some neurodegenerative diseases.Studies have shown that mutations in the MAPT gene are associated with susceptibility to Parkinson’s disease.It has been suggested that the H1 haplotype of the MAPT gene has been prevalent in patients with progressive supranuclear palsy(an atypical form of Parkinson’s disease).However,some studies have shown that the H1 genotype of MAPT gene can increase the susceptibility to PD.At present,it is still controversial whether different genotypes of MAPT gene mutations have influence on the incidence of PD.In this paper,a meta-analysis was conducted to clarify the influence of different genotypes of MAPT gene polymorphism on the incidence of PD.Methods:With"Parkinson’s disease","MAPT","H1 genotype"and"H2genotype"as Chinese subject words,we searched China Biomedical Literature Database(CBM),China National Knowledge Network(CNKI),Wanfang Data Knowledge Service Platform and VIP database.With"Parkinson’s disease","MAPT","H1"and"H2"as the main topics,the literature related to"the influence of MAPT gene H1 genotype on the incidence of PD"was retrieved through English databases such as Pub Med,Medline,Embase,Web of Science and Cochrane Library,and the literature data was extracted and the literature quality was evaluated.Result:A total of 7 case-control studies were included,all of which were related to the correlation between MAPT gene H1/H1 genotype,H1/H2genotype and H2/H2 genotype and the incidence of Parkinson’s disease.After data extraction and integration,the above studies included 2,745patients with Parkinson’s disease as the experimental group and 2,872patients without Parkinson’s disease as the control group.The results of Meta-analysis showed that the correlation between the frequency of H1and H2 haplotypes of MAPT gene and the incidence of Parkinson’s disease was quite heterogeneous(Q test P<0/00001,I~2=87%),and the clinical significance was limited.There was no significant heterogeneity between MAPT genotypes and Parkinson’s disease(Q test P=0.10,I~2<40%),H1/H1 genotypes and H1/H2(OR=1.49,95%CI:1.33-1,67,P<0.00001)and H2/H2(OR=1.80,95%CI:1.38-2.36,P<0.0001)genotypes were associated with an increased risk of Parkinson’s disease,while H1/H2 and H2/H2 genotypes had no statistically significant effects on the risk of Parkinson’s disease.Conclusion:People with MAPT gene H1/H1 genotype are more likely to suffer from PD than those with other genotypes.The influence of H1/H2 and H2/H2 genotypes on the incidence of PD still needs further study. |
