@article {6027, title = {Genetic loci for retinal arteriolar microcirculation.}, journal = {PLoS One}, volume = {8}, year = {2013}, month = {2013}, pages = {e65804}, abstract = {

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{\texttimes}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{\texttimes}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.

}, keywords = {Aged, Aged, 80 and over, Arterioles, Chromosomes, Human, Pair 5, European Continental Ancestry Group, Female, Genetic Loci, Genome-Wide Association Study, Genotype, Humans, Male, MEF2 Transcription Factors, Microcirculation, Middle Aged, Models, Genetic, Retinal Vessels}, issn = {1932-6203}, doi = {10.1371/journal.pone.0065804}, author = {Sim, Xueling and Jensen, Richard A and Ikram, M Kamran and Cotch, Mary Frances and Li, Xiaohui and Macgregor, Stuart and Xie, Jing and Smith, Albert Vernon and Boerwinkle, Eric and Mitchell, Paul and Klein, Ronald and Klein, Barbara E K and Glazer, Nicole L and Lumley, Thomas and McKnight, Barbara and Psaty, Bruce M and de Jong, Paulus T V M and Hofman, Albert and Rivadeneira, Fernando and Uitterlinden, Andr{\'e} G and van Duijn, Cornelia M and Aspelund, Thor and Eiriksdottir, Gudny and Harris, Tamara B and Jonasson, Fridbert and Launer, Lenore J and Attia, John and Baird, Paul N and Harrap, Stephen and Holliday, Elizabeth G and Inouye, Michael and Rochtchina, Elena and Scott, Rodney J and Viswanathan, Ananth and Li, Guo and Smith, Nicholas L and Wiggins, Kerri L and Kuo, Jane Z and Taylor, Kent D and Hewitt, Alex W and Martin, Nicholas G and Montgomery, Grant W and Sun, Cong and Young, Terri L and Mackey, David A and van Zuydam, Natalie R and Doney, Alex S F and Palmer, Colin N A and Morris, Andrew D and Rotter, Jerome I and Tai, E Shyong and Gudnason, Vilmundur and Vingerling, Johannes R and Siscovick, David S and Wang, Jie Jin and Wong, Tien Y} } @article {5875, title = {Insights into the genetic architecture of early stage age-related macular degeneration: a genome-wide association study meta-analysis.}, journal = {PLoS One}, volume = {8}, year = {2013}, month = {2013}, pages = {e53830}, abstract = {

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{\texttimes}10(-31)) and age-related maculopathy susceptibility 2 (ARMS2) (P = 4.3{\texttimes}10(-24)) loci, and suggested Apolipoprotein E (ApoE) polymorphisms (rs2075650; P = 1.1{\texttimes}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{\texttimes}10(-6)) and upstream of GLI2 (rs6721654; P = 6.5{\texttimes}10(-6)), encoding retinal Sonic hedgehog signalling regulators, and in the tyrosinase (TYR) gene (rs621313; P = 3.5{\texttimes}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.

}, keywords = {Apolipoproteins E, Complement Factor H, Genetic Predisposition to Disease, Genome-Wide Association Study, Genotype, Humans, Kruppel-Like Transcription Factors, Macular Degeneration, Nerve Tissue Proteins, Polymorphism, Single Nucleotide, Proteins, Risk Factors, Zinc Finger Protein Gli3}, issn = {1932-6203}, doi = {10.1371/journal.pone.0053830}, author = {Holliday, Elizabeth G and Smith, Albert V and Cornes, Belinda K and Buitendijk, Gabri{\"e}lle H S and Jensen, Richard A and Sim, Xueling and Aspelund, Thor and Aung, Tin and Baird, Paul N and Boerwinkle, Eric and Cheng, Ching Yu and van Duijn, Cornelia M and Eiriksdottir, Gudny and Gudnason, Vilmundur and Harris, Tamara and Hewitt, Alex W and Inouye, Michael and Jonasson, Fridbert and Klein, Barbara E K and Launer, Lenore and Li, Xiaohui and Liew, Gerald and Lumley, Thomas and McElduff, Patrick and McKnight, Barbara and Mitchell, Paul and Psaty, Bruce M and Rochtchina, Elena and Rotter, Jerome I and Scott, Rodney J and Tay, Wanting and Taylor, Kent and Teo, Yik Ying and Uitterlinden, Andr{\'e} G and Viswanathan, Ananth and Xie, Sophia and Vingerling, Johannes R and Klaver, Caroline C W and Tai, E Shyong and Siscovick, David and Klein, Ronald and Cotch, Mary Frances and Wong, Tien Y and Attia, John and Wang, Jie Jin} } @article {8631, title = {Association of Genetic Variation With Keratoconus.}, journal = {JAMA Ophthalmol}, volume = {138}, year = {2020}, month = {2020 02 01}, pages = {174-181}, abstract = {

Importance: Keratoconus is a condition in which the cornea progressively thins and protrudes in a conical shape, severely affecting refraction and vision. It is a major indication for corneal transplant. To discover new genetic loci associated with keratoconus and better understand the causative mechanism of this disease, we performed a genome-wide association study on patients with keratoconus.

Objective: To identify genetic susceptibility regions for keratoconus in the human genome.

Design, Setting, and Participants: This study was conducted with data from eye clinics in Australia, the United States, and Northern Ireland. The discovery cohort of individuals with keratoconus and control participants from Australia was genotyped using the Illumina HumanCoreExome single-nucleotide polymorphism array. After quality control and data cleaning, genotypes were imputed against the 1000 Genomes Project reference panel (phase III; version 5), and association analyses were completed using PLINK version 1.90. Single-nucleotide polymorphisms with P < 1.00 {\texttimes} 10-6 were assessed for replication in 3 additional cohorts. Control participants were drawn from the cohorts of the Blue Mountains Eye Study and a previous study of glaucoma. Replication cohorts were from a previous keratoconus genome-wide association study data set from the United States, a cohort of affected and control participants from Australia and Northern Ireland, and a case-control cohort from Victoria, Australia. Data were collected from January 2006 to March 2019.

Main Outcomes and Measures: Associations between keratoconus and 6 252 612 genetic variants were estimated using logistic regression after adjusting for ancestry using the first 3 principal components.

Results: The discovery cohort included 522 affected individuals and 655 control participants, while the replication cohorts included 818 affected individuals (222 from the United States, 331 from Australia and Northern Ireland, and 265 from Victoria, Australia) and 3858 control participants (2927 from the United States, 229 from Australia and Northern Ireland, and 702 from Victoria, Australia). Two novel loci reached genome-wide significance (defined as P < 5.00 {\texttimes} 10-8), with a P value of 7.46 {\texttimes} 10-9 at rs61876744 in patatin-like phospholipase domain-containing 2 gene (PNPLA2) on chromosome 11 and a P value of 6.35 {\texttimes} 10-12 at rs138380, 2.2 kb upstream of casein kinase I isoform epsilon gene (CSNK1E) on chromosome 22. One additional locus was identified with a P value less than 1.00 {\texttimes} 10-6 in mastermind-like transcriptional coactivator 2 (MAML2) on chromosome 11 (P = 3.91 {\texttimes} 10-7). The novel locus in PNPLA2 reached genome-wide significance in an analysis of all 4 cohorts (P = 2.45 {\texttimes} 10-8).

Conclusions and Relevance: In this relatively large keratoconus genome-wide association study, we identified a genome-wide significant locus for keratoconus in the region of PNPLA2 on chromosome 11.

}, keywords = {Adult, Female, Fuchs{\textquoteright} Endothelial Dystrophy, Genetic Predisposition to Disease, Genome-Wide Association Study, Humans, Keratoconus, Lipase, Logistic Models, Male, Middle Aged, Polymorphism, Single Nucleotide}, issn = {2168-6173}, doi = {10.1001/jamaophthalmol.2019.5293}, author = {McComish, Bennet J and Sahebjada, Srujana and Bykhovskaya, Yelena and Willoughby, Colin E and Richardson, Andrea J and Tenen, Abi and Charlesworth, Jac C and Macgregor, Stuart and Mitchell, Paul and Lucas, Sionne E M and Mills, Richard A and Mackey, David A and Li, Xiaohui and Wang, Jie Jin and Jensen, Richard A and Rotter, Jerome I and Taylor, Kent D and Hewitt, Alex W and Rabinowitz, Yaron S and Baird, Paul N and Craig, Jamie E and Burdon, Kathryn P} }