Chiba-Falek Ornit, Lutz Michael W
Department of Neurology, Duke University Medical Center, Durham, NC 27710, USA.
Center for Genomic and Computational Biology, Duke University Medical Center, Durham, NC 27710, USA.
Expert Rev Precis Med Drug Dev. 2017;2(1):47-55. doi: 10.1080/23808993.2017.1286227. Epub 2017 Feb 1.
Developing biomarker tools for identification of individuals at high-risk for late-onset Alzheimer's disease (LOAD) is important for prognosis and early treatment. This review focuses on genetic factors and their potential role for precision medicine in LOAD.
e4 is the strongest genetic risk factor for non-Mendelian LOAD, and the -linkage disequilibrium (LD) region has produced the most significant association signal in multi-center genome-wide-association-studies (GWAS). Consideration of extended haplotypes in the -LD region and specifically, non-coding variants in putative enhancer elements, such as the -polyT, in-addition to the coding variants that comprise the -genotypes, may be useful for predicting subjects at high-risk of developing LOAD and estimating age-of-onset of early disease-stage symptoms. A genetic-biomarker based on -polyT haplotypes, and age is currently applied in a clinical trial for prevention/delay of LOAD onset. Additionally, we discuss LOAD-GWAS discoveries and the development of new genetic risk scores based on LOAD-GWAS findings other than the -LD region.
Deciphering the precise causal genetic-variants within LOAD-GWAS regions will advance the development of genetic-biomarkers to complement and refine the -LD region based prediction model. Collectively, the genetic-biomarkers will be translational for early diagnosis and enrichment of clinical trials with subjects at high-risk.
开发用于识别晚发性阿尔茨海默病(LOAD)高危个体的生物标志物工具对于预后和早期治疗至关重要。本综述聚焦于遗传因素及其在LOAD精准医学中的潜在作用。
ε4是散发性LOAD最强的遗传风险因素,且连锁不平衡(LD)区域在多中心全基因组关联研究(GWAS)中产生了最显著的关联信号。除了构成ε基因型的编码变异外,考虑ε-LD区域的扩展单倍型,特别是推定增强子元件中的非编码变异,如ε-多聚T,可能有助于预测LOAD高危个体并估计疾病早期症状的发病年龄。一种基于ε-多聚T单倍型和年龄的遗传生物标志物目前正在一项预防/延缓LOAD发病的临床试验中应用。此外,我们还讨论了LOAD-GWAS的发现以及基于LOAD-GWAS结果(除ε-LD区域外)开发的新遗传风险评分。
解读LOAD-GWAS区域内精确的因果遗传变异将推动遗传生物标志物的开发,以补充和完善基于ε-LD区域的预测模型。总体而言,这些遗传生物标志物将有助于早期诊断,并在高危个体的临床试验中实现富集。