Centre for Eye Research Australia (CERA) - Research Publications

Permanent URI for this collection

http://hdl.handle.net/11343/198002

Filters

2013 2
Reset filters

Settings
Statistics
Citations
Author: Hewitt, Alexander × Author: Xie, Jing × End date: 2013 × Start date: 2013 × Type: Journal Article ×

Search Results

Now showing 1 - 2 of 2
  • Item
    No Preview Available
    Genetic Loci for Retinal Arteriolar Microcirculation
    Sim, X ; Jensen, RA ; Ikram, MK ; Cotch, MF ; Li, X ; MacGregor, S ; Xie, J ; Smith, AV ; Boerwinkle, E ; Mitchell, P ; Klein, R ; Klein, BEK ; Glazer, NL ; Lumley, T ; McKnight, B ; Psaty, BM ; de Jong, PTVM ; Hofman, A ; Rivadeneira, F ; Uitterlinden, AG ; van Duijn, CM ; Aspelund, T ; Eiriksdottir, G ; Harris, TB ; Jonasson, F ; Launer, LJ ; Attia, J ; Baird, PN ; Harrap, S ; Holliday, EG ; Inouye, M ; Rochtchina, E ; Scott, RJ ; Viswanathan, A ; Li, G ; Smith, NL ; Wiggins, KL ; Kuo, JZ ; Taylor, KD ; Hewitt, AW ; Martin, NG ; Montgomery, GW ; Sun, C ; Young, TL ; Mackey, DA ; van Zuydam, NR ; Doney, ASF ; Palmer, CNA ; Morris, AD ; Rotter, JI ; Tai, ES ; Gudnason, V ; Vingerling, JR ; Siscovick, DS ; Wang, JJ ; Wong, TY ; Wallace, GR (PUBLIC LIBRARY SCIENCE, 2013-06-12)
    Narrow arterioles in the retina have been shown to predict hypertension as well as other vascular diseases, likely through an increase in the peripheral resistance of the microcirculatory flow. In this study, we performed a genome-wide association study in 18,722 unrelated individuals of European ancestry from the Cohorts for Heart and Aging Research in Genomic Epidemiology consortium and the Blue Mountain Eye Study, to identify genetic determinants associated with variations in retinal arteriolar caliber. Retinal vascular calibers were measured on digitized retinal photographs using a standardized protocol. One variant (rs2194025 on chromosome 5q14 near the myocyte enhancer factor 2C MEF2C gene) was associated with retinal arteriolar caliber in the meta-analysis of the discovery cohorts at genome-wide significance of P-value <5×10(-8). This variant was replicated in an additional 3,939 individuals of European ancestry from the Australian Twins Study and Multi-Ethnic Study of Atherosclerosis (rs2194025, P-value = 2.11×10(-12) in combined meta-analysis of discovery and replication cohorts). In independent studies of modest sample sizes, no significant association was found between this variant and clinical outcomes including coronary artery disease, stroke, myocardial infarction or hypertension. In conclusion, we found one novel loci which underlie genetic variation in microvasculature which may be relevant to vascular disease. The relevance of these findings to clinical outcomes remains to be determined.
  • Item
    No Preview Available
    Short Sleep Duration Is Associated with Risk of Future Diabetes but Not Cardiovascular Disease: a Prospective Study and Meta-Analysis
    Holliday, EG ; Magee, CA ; Kritharides, L ; Banks, E ; Attia, J ; Miao, X-P (PUBLIC LIBRARY SCIENCE, 2013-11-25)
    Genetic factors explain a majority of risk variance for age-related macular degeneration (AMD). While genome-wide association studies (GWAS) for late AMD implicate genes in complement, inflammatory and lipid pathways, the genetic architecture of early AMD has been relatively under studied. We conducted a GWAS meta-analysis of early AMD, including 4,089 individuals with prevalent signs of early AMD (soft drusen and/or retinal pigment epithelial changes) and 20,453 individuals without these signs. For various published late AMD risk loci, we also compared effect sizes between early and late AMD using an additional 484 individuals with prevalent late AMD. GWAS meta-analysis confirmed previously reported association of variants at the complement factor H (CFH) (peak P = 1.5×10(-31)) and age-related maculopathy susceptibility 2 (ARMS2) (P = 4.3×10(-24)) loci, and suggested Apolipoprotein E (ApoE) polymorphisms (rs2075650; P = 1.1×10(-6)) associated with early AMD. Other possible loci that did not reach GWAS significance included variants in the zinc finger protein gene GLI3 (rs2049622; P = 8.9×10(-6)) and upstream of GLI2 (rs6721654; P = 6.5×10(-6)), encoding retinal Sonic hedgehog signalling regulators, and in the tyrosinase (TYR) gene (rs621313; P = 3.5×10(-6)), involved in melanin biosynthesis. For a range of published, late AMD risk loci, estimated effect sizes were significantly lower for early than late AMD. This study confirms the involvement of multiple established AMD risk variants in early AMD, but suggests weaker genetic effects on the risk of early AMD relative to late AMD. Several biological processes were suggested to be potentially specific for early AMD, including pathways regulating RPE cell melanin content and signalling pathways potentially involved in retinal regeneration, generating hypotheses for further investigation.