Hong-Lei Li

PICALM and CR1 Variants are not Associated with Sporadic Alzheimer's Disease in Chinese Patients

Alzheimers disease (AD) is the most common form of senile dementia, and the overall prevalence increases exponentially with age. It is well known that genetic variants may play an important role in the pathogenesis of this disorder. Recently, two independent large-scale genome-wide association studies (GWAS) identified 3 novel single nucleotide polymorphisms (SNPs) (rs11136000 within CLU, rs3851179 within PICALM and rs6656401 within CR1) that are associated with late-onset AD (LOAD), and these results have been replicated by other studies performed in the Caucasian population. Recently, an independent study failed to verify the association for the SNP within CLU in a Han Chinese population, indicating that there may be genetic heterogeneity in this association. In the present study, we studied the SNPs within PICALM and CR1 in 474 sporadic AD patients (SAD) and 591 unrelated age- and sex-matched healthy controls of Han Chinese descent. Our data revealed that the frequencies of both of these SNPs were not significantly difference between the SAD and control groups. Thus, the association between SNPs within PICALM, CR1, and SAD should be studied further in different ethnic groups.

Clusterin variants are not associated with southern Chinese patients with Alzheimer's disease

Recent genome-wide association studies identified clusterin (CLU) to be associated with sporadic Alzheimers disease. To help clarify the relevance of CLU as genetic determinant of AD, we analyzed its association in southern Chinese Han population. This study comprised 499 sporadic Alzheimers disease patients and 592 unrelated age- and sex-matched healthy controls. Four single-nucleotide polymorphisms (rs2279590, rs9331888, rs11136000, and rs1532278) within CLU were selected for genotyping. No positive association was found between the CLU variants and AD. Our study suggests that CLU variants may not be an AD susceptibility factor in southern Chinese Han population.

The Polymorphism of the ATP-Binding Cassette Transporter 1 Gene Modulates Alzheimer Disease Risk in Chinese Han Ethnic Population

BACKGROUND Recent studies highlight a potential role of cholesterol metabolic disturbance in the pathophysiology of Alzheimer disease (AD). The adenosine triphosphate (ATP)-binding cassette transporter 1 (ABCA1) gene resides within proximity of linkage peaks on chromosome 9q influence AD and plays a key role in cellular cholesterol efflux in the brain. METHODS We studied the role of R219K and V825I polymorphisms of ABCA1 in modulating the risk of AD in 321 AD patients and 349 comparisons of Chinese Han. Genotyping of R219K and V825I were performed by PCR-restriction fragment length polymorphism analysis. RESULTS The genotype distribution of R219K was different with more RK in total AD group (χ(2) = 8.705, df = 2, p = 0.013), late-onset AD (LOAD) group (χ(2) = 10.636, df = 2, p = 0.005), APOE non-ε4ε4 group (χ(2) = 9.900, df = 2, p = 0.007), and female AD group (χ(2) = 8.369, df = 2, p = 0.015). Logistic regression manifested the risk of AD increased in RK carriers in total AD group (Wald = 6.102, df = 1, p = 0.014, odds ratio [OR]: 1.546, 95% confidence interval [95% CI]: 1.094-2.185), LOAD group (Wald = 7.746, df = 1, p = 0.005, OR: 1.921, 95% CI: 1.213-3.041), and APOE non-ε4ε4 group (Wald = 6.399, df = 1, p = 0.011, OR: 1.586, 95% CI: 1.109-2.266). K allele (RK + KK) also increased the risk of AD compared with RR allele in LOAD group (Wald = 4.750, df = 1, p = 0.029, OR: 1.619, 95% CI: 1.050-2.497). However, no discrepancy was found in V825I. In R219K, age at onset (AAO) was significantly lower by 4.9 years on average in patients of KK genotype than those of RK in APOE ε4 carrying group and higher by 5.5 years in patients of KK genotype than those of RR in APOE ε4 noncarrying group. In V825I, AAO was diseased by 4.3 years in II genotype compared with VV genotype in APOE ε4 noncarrying group and 3.4 years in APOE ε4ε4 noncarrying group. CONCLUSION The results indicated that the RK genotype or K allele (RK + KK) of R219K may relate to the development of AD in the east of China.

Association study of ABCA7 and NPC1 polymorphisms with Alzheimer's disease in Chinese Han ethnic population.

Department of Neurology and Institute of Neurology, Huashan Hospital, Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Shanghai Medical College, Fudan University, Shanghai and Department of Neurology, General Hospital of Ningxia Medical University, Ningxia, China Correspondence to Zhi-Ying Wu, MD, PhD, Department of Neurology and Institute of Neurology, Huashan Hospital, Institutes of Brain Science and State Key Laboratory of Medical Neurobiology, Shanghai Medical College, Fudan University, 12 Wulumuqi Zhong Road, Shanghai 200040, China Tel/fax: + 86 21 62483421; e-mail: zhiyingwu@fudan.edu.cn

The LRRK2 R1628P variant plays a protective role in Han Chinese population with Alzheimer's disease.

Alzheimers disease (AD) and Parkinsons disease (PD) are the most prevalent neurodegenerative disorders that may share some overlapping etiologies. Mutations within leucine‐rich repeat kinase 2 (LRRK2) have been reported to be responsible for PD, and the location of LRRK2 is within a linkage peak for sporadic AD (SAD). The aim of this study was to investigate two Asian‐specific LRRK2 variants, R1628P and G2385R, with the association of Han Chinese SAD.

Common variants at Bin1 are associated with sporadic Alzheimer's disease in the Han Chinese population.

Objectives Recent genome-wide association studies identified bridging integrator 1 (Bin1) to be associated with sporadic Alzheimer’s disease (SAD). To clarify the relevance of Bin1 as a genetic determinant of AD, we analyzed its association in a Han Chinese population from the South East part of mainland China. Methods This study investigated 427 SAD patients and 451 unrelated age-matched and sex-matched healthy controls. Two single nucleotide polymorphisms (rs7561528 and rs744373) adjacent to Bin1 that emerged from previous genome-wide association studies were genotyped using the MassARRAY Analyzer 4 Sequenom platform. Results As expected, the genotype distribution of rs7561528 was significantly different between the SAD group and the controls, with more AG in controls [odds ratio (OR) 0.605, 95% confidence interval (CI) 0.429–0.854, P=0.004], and the difference increased using an additive genetic model (OR 0.593, 95% CI 0.425–0.828, P=0.002). However, we did not observe a difference in the genotype distribution of the rs744373 between the SAD and the control group (OR 1.189, 95% CI 0.809–1.747, P=0.378). Conclusions To the best of our knowledge, our study is the first to confirm the association of the variant rs7561528 adjacent to Bin1 with SAD in a Han Chinese Population.

Associations between apolipoprotein E gene polymorphisms and Alzheimer's disease risk in a large Chinese Han population.

Objective Apolipoprotein E gene (APOE) polymorphisms contributing to the risk of sporadic Alzheimer’s disease (AD) have been identified for decades, but it has not been investigated in large AD samples of Chinese Han population. Methods We performed a cross-sectional study to explore the effect of APOE polymorphisms on sporadic AD in 875 sporadic AD patients and 1,195 cognitive normal controls of Chinese Han. Genotyping of APOE was determined by multiplex amplification refractory mutation system polymerase chain reaction. Results APOE ε3ε4 and ε4ε4 genotypes increased AD risk with dosage effect. The odds ratio (OR) of ε3ε4 was 1.89 and the OR of ε4ε4 was 15.64 compared with that of ε3ε3 in all the subjects. E2ε3 genotype decreased AD risk in all the subjects (OR=0.64), female subgroup (OR=0.57), and late-onset AD subgroup (OR=0.60). However, neither ε2ε2 nor ε2ε4 affected AD risk. About the age at onset (AAO), the influence of APOE ε4 was only exhibited in late-onset AD subgroup, with 1 year lower in ε4-positive ones than negative ones. Further analysis did not show the dosage effect of ε4 pertinent to AAO, though the AAO of ε4ε4 patients decreased by 2 years. E2 did not affect the AAO of AD. Conclusion APOE ε4 is a strong risk factor of AD risk in Chinese Han population, and APOE ε4ε4 genotype might be related to the AAO of late-onset AD.

A variant within FGF1 is associated with Alzheimer's disease in the Han Chinese population

Alzheimers disease (AD) is the most common neurodegenerative disorder characterized by the accumulation of amyloid beta (Aβ) plaques and Tau‐containing neurofibrillary tangles in vulnerable brain areas. The progression of AD is well correlated with hippocampal neuron loss which highly suggests genes associated with neuron survival would be important for AD pathogenesis. According to the recent results of genome‐wide association studies (GWAS) and other reported studies, we selected two single nucleotide polymorphisms (SNPs), rs3765728 within tumor protein p73 (P73), and rs34011 within fibroblast growth factor 1 (FGF1), both genes were related to neuron survival. We analyzed the distribution of rs3765728 and rs34011 in 1,083 Chinese subjects including 429 unrelated sporadic AD patients and 654 unrelated age and gender‐matched control subjects. We found that the genotype distribution of rs34011 was significantly different between AD and control group (χ2 = 9.048, df = 2, P = 0.011). Logistic regression manifested the risk of AD increased in TT genotype carriers in total subjects (Wald = 8.892, df = 1, P = 0.003, odds ratio [OR]:2.009, 95% confidence interval [95%CI]: 1.270–3.178). This effect was also found in APOE ϵ4 carrier group (Wald = 7.844, df = 1, P = 0.005, OR: 4.201, 95%CI: 1.539–11.472), suggesting the rs34011 has a synergetic effect of APOE on AD risk. However, no association was observed between rs3765728 and AD in the Han Chinese population (χ2 = 0.431, df = 2, P = 0.806).

Lack of association between CALHM1 p.P86L variation and Alzheimer's disease in the Han Chinese population

In recent years, several studies have reported calcium homeostasis modulator 1 (CALHM1) was a potential gene related to Alzheimers disease (AD) susceptibility. However, whether CALHM1 p.P86L variation (rs2986017), a risk factor for AD is still controversial. Two independent studies have been performed in the Chinese population and the conclusions have not reached an agreement. In the present study, we performed a replication case-control study in 1301 Chinese subjects including 452 sporadic AD patients and 849 unrelated age and gender-matched controls, to determine whether this variation is a risk factor for AD in the Han Chinese population. We failed to replicate the positive association between the CALHM1 p.P86L variation and AD. In addition, we also examined p.P86L variation in a meta-analysis of 5 independent studies performed in Chinese and other Asian populations and negative association was found in total 2328 AD patients and 2865 controls. Our study suggests that CALHM1 p.P86L variation may not be an AD susceptibility factor in the Han Chinese population.

Genetic Association of CUGBP2 and DNMBP with Alzheimer’ s Disease in the Chinese Han Population

OBJECTIVE Recently, candidate genetic studies revealed the single nucleotide polymorphisms (SNPs) of CUGBP2 (rs2242451) and DNMBP (rs11190305 and rs3740058) associated with Alzheimers disease (AD). Due to genetic heterogeneity and different ethnic background, the purpose of our study was to confirm the association between these 3 SNPs with AD risk in the Chinese Han population. METHODS We investigated 482 sporadic AD (SAD) patients and 813 unrelated cognitive normal controls of the Chinese Han population. The genotypes of the 3 SNPs (rs2242451, rs11190305, rs3740058) were carried out by MassARRAY iPLEX system. RESULTS The genotype and the allele frequency of rs2242451 were significantly different between AD and control group in total subject (genotype: p=0.019, allele frequency: p=0.022, OR=0.760, 95%CI=0.601- 0.962) with A allele decreasing AD risk. After stratification by age at onset, gender, APOE ε4 carrying status and homozygous APOE ε4, the protective effect of A allele remained in female and APOE ε4ε4 non-carrying subgroups. The rs3740058 in DNMBP was significantly differently in genotype between AD and control in APOE ε4ε4 subgroup, but showed no effect on AD risk, either did rs11190305 polymorphisms in DNMBP. Meta-analysis was performed in rs11190305 and rs3740058 of DNMBP respectively. Positive relationship with AD was found in rs11190305 (OR=1.11, 95%CI=1.01-1.21), but not in rs3740058 (OR=1.05, 95%CI=0.98-1.13). Moreover, the genotypes of these 3 SNPs had no effect on age at onset of AD. CONCLUSION The A allele of rs2242451 in CUGBP2 might decrease SAD risk in the Chinese Han population.