Table of Contents
International Journal of Medical Genetics
Volume 2014, Article ID 689832, 6 pages
http://dx.doi.org/10.1155/2014/689832
Research Article

Genetic Variants in the SORL1 Gene Are Associated with Age at Onset of Alzheimer Disease: A Survival Analysis

1Department of Biostatistics and Epidemiology, College of Public Health, East Tennessee State University, P.O. Box 70259, Lamb Hall, Johnson City, TN 37614-1700, USA
2Departments of Psychiatry and Neurology and the Center of Excellence in Neuroscience, Paul L. Foster School of Medicine, Texas Tech University Health Sciences Center, El Paso, TX 79905, USA

Received 17 January 2014; Revised 27 July 2014; Accepted 31 July 2014; Published 12 August 2014

Academic Editor: Jezabel V. López

Copyright © 2014 Ke-Sheng Wang et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Few studies focused on the association of SORL1 with the age at onset (AAO) of Alzheimer disease (AD). This study investigated the association of 43 SNPs in SORL1 with the AAO of AD by using the Kaplan-Meier survival analysis and the Cox proportional hazards model in SAS version 9.2 and linear regression model in PLINK software (791 AD patients and 782 controls). Both logrank test and Cox regression model showed that five SNPs (rs1784934, rs676759, rs560573, rs593769, and rs11218313) were associated with the AAO of AD in the male sample, while one SNP (rs17125558) was associated with the AAO of AD in the female sample (). SNP rs560573, previously associated with the risk of late-onset AD, showed the most association with the AAO in the male sample ( for logrank test and in the Cox model). The mean AAO was approximately 2.5 years earlier in individuals who were homozygous for the minor allele compared with those who had at least one major allele. Linear regression model showed that rs2282649 and rs726601 were associated with AAO in the whole sample ( and 0.0367, resp.). These findings provide evidence of several genetic variants in SORL1 influencing the AAO of AD.