The Association Between CD33 Single Nucleotide Polymorphism(SNP) And Sporadic Alzheimer’s Disease In Han Chinese

Background: Alzheimer’s disease(AD)is an age-related neurodegenerative disease,which has two major pathological features as extracellular senile plaques and intraneuronal fibrillary tangles.Senile plaques consist of β amyloid(Aβ)peptides that are derived from amyloid precursor protein(APP)through sequential cleavages by β-and γ-secretases.Identification of new factors that regulate Aβ generation are a major goal in AD research.The cluster of differentiation 33(CD33)gene is compelling among the susceptibility genes of Alzheimer’s disease(AD)in Genome-wide association study(GWAS).The cluster of differentiation 33(CD33)gene is an immune function protein located in 19p13.33 with several functions,such as cell adhesion,anti-inflammatory signaling,and endocytosis functions.Researches of the relationship between AD and polymorphism in CD33 have showed conflicting results.Objects: To explore the association between CD33 single nucleotide polymorphism(SNP)and sporadic Alzheimer’s disease(AD)in han Chinese.Methods : A case-control study was conducted in a Han Chinese population with 166 SAD patients and 167 healthy controls.The LDR-PCR method was using to investigate the association of allele and genotype of CD33 rs3865444 with SAD risk.Results: The G allele frequency of CD33 SNP rs3865444 was significantly lower in SAD than healthy controls(P=0.010,OR=0.63,95%CI=0.45-0.90).The frequency of genotype GG carriers was significantly lower in SAD than healthy controls(P=0.013,OR=0.57,95% CI =0.38-0.89).Conclusions: The CD33 SNP rs3865444 is associated with SAD risk in a Han Chinese in which the G allele might be a protective factor.