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Polypoidal Choroidal Vasculopathy
Published in Ching-Yu Cheng, Tien Yin Wong, Ophthalmic Epidemiology, 2022
Genetic studies also have tried to identify prognostic factors. So far, most studies have employed a small-scale candidate gene approach. Such studies demonstrated that SNPs in the ARMS2 locus, among other SNPs, may be an important risk factor for severe phenotype. For example, the ARMS2 locus was associated with larger lesion size, higher likelihood of vitreous hemorrhage, and worse visual outcome 1 year after treatment with PDT or combination therapy in PCV.65 It also confers a higher risk for second-eye involvement.66 A prospective multicenter genome-wide association study (GWAS) including 461 treatment-naive exudative AMD patients failed to identify genetic loci associated with treatment outcomes but confirmed that ARMS2/HTRA1 polymorphism might be able to predict the frequency of injection after initial ranibizumab treatment.67 Another GWAS study including 919 exudative AMD patients also failed to identify genetic loci associated with treatment outcomes, but found that four variants showed a suggestive level of associations with visual loss, among which three were VEGF-related pathway (KCNMA1, SOCS2, and OTX2).68
Genetics
Published in Cathy Laver-Bradbury, Margaret J.J. Thompson, Christopher Gale, Christine M. Hooper, Child and Adolescent Mental Health, 2021
Early molecular genetic approaches were mainly hypothesis-driven, selecting genes of interest a priori based on existing knowledge of biological pathways and investigating their association with disorders in either case-control or family-based association designs. These candidate-gene approaches have yielded few clear replicated findings and are, by their nature, less suitable for gene discovery than genome-wide approaches because of a high risk of false-positive discoveries.
Statistical Considerations and Biological Mechanisms Underlying Individual Differences in Adaptations to Exercise Training
Published in Peter M. Tiidus, Rebecca E. K. MacPherson, Paul J. LeBlanc, Andrea R. Josse, The Routledge Handbook on Biochemistry of Exercise, 2020
Jacob T. Bonafiglia, Hashim Islam, Nir Eynon, Brendon J. Gurd
The sequencing of the human genome provided experimental opportunities beyond twin/familial aggregation studies for investigating whether specific genetic variants underlie complex human phenotypes. Experiments investigating genetic associations to human phenotypes follow either a candidate-gene or a hypothesis-free approach (86). Candidate-gene approaches involve testing the hypothesis that pre-determined, specific genetic variants are associated with a given phenotype. Conversely, hypothesis-free approaches involve genome-wide association studies (GWAS) to identify genetic associations with human phenotypes in hundreds of thousands to millions of variations across the human genome. For the remainder of this section, we will discuss genetic associations with exercise-induced changes in VO2 max, as this is the most commonly studied outcome in exercise genomics (72). For more information on other exercise-related outcomes, we refer the reader to annual reviews completed by leaders in exercise genomics (most recent report, 73).
The common variant of rs6214 in insulin like growth factor 1 (IGF1) gene: a potential protective factor for non-alcoholic fatty liver disease
Published in Archives of Physiology and Biochemistry, 2023
Mohammad Sabzikarian, Touraj Mahmoudi, Seidamir Pasha Tabaeian, Gholamreza Rezamand, Asadollah Asadi, Hamid Farahani, Hossein Nobakht, Reza Dabiri, Fariborz Mansour-Ghanaei, Faramarz Derakhshan, Mohammad Reza Zali
Accumulating evidence revealed that NAFLD like other complex diseases results from environmental factors acting on a susceptible polygenic background. Candidate gene association study is one of the reliable methods for identifying novel susceptible genes in these diseases. In recent years, the investigation into the association between gene polymorphisms and NAFLD has become a subject of interest. Insulin-signalling pathway genes are potential candidate genes for NAFLD due to the crucial role of IR in the development and progression of NAFLD (Dongiovanni et al. 2010). Both insulin sensitivity and insulin secretion have a genetic component (Schäfer et al. 2011). IR expedites the release of free fatty acid from adipose tissue and its influx into liver (Eguchi et al. 2006, Brunt et al. 2009, Salamone and Bugianesi 2010). Interestingly, HOMA-IR index is an independent predictor of the severity of liver fibrosis and the risk of NAFLD progression is increased in the patients with IR. It appears that insulin secretion is increased in NAFLD patients to compensate for reduced insulin sensitivity to maintain glucose homeostasis in these patients (Atay et al. 2017, Fujii et al. 2019). Despite the biological plausibility, however, no studies to date have evaluated the association between IGF1 and IGFBP3 gene variants and NAFLD risk.
Evaluation of JUN, FN1 and LAMB1 polymorphisms in pterygium in a Chinese Han population
Published in Ophthalmic Genetics, 2022
Xiying Wu, Shiqi Dong, Yuting Xu, Ge Zhu, Ming Yan
A total of 240 DEGs were investigated by the GO and KEGG pathway enrichment analysis with DAVID. And the results were selected based on the most significant but those with counts of DEGs less than five were rejected. GO term enrichment analysis was dominated by functional categories, including the regulation of cell adhesion, inflammatory response, angiogenesis, positive regulation of transcription, DNA-templated, response to drug, cell proliferation, negative regulation of apoptotic process, cell proliferation, transcription from RNA polymerase II promoter, oxidation-reduction process (Figure 2). The DEGs were significantly enriched in nine KEGG pathways, including cell adhesion molecules (CAMs), amoebiasis, focal adhesion, ECM–receptor interaction, protein digestion and absorption, calcium signaling pathway, TNF signaling pathway, MAPK signaling pathway, and thyroid hormone signaling pathway (Figure 2). And some of these results were consistent with the pathogenesis of pterygium previously reported, such as abnormal ECM, abnormal proliferation, and MAPK (9,17). Focal adhesion pathway is extremely meaningful within our selected pathways and the DEGs enriched most just equal with MAPK signaling pathway, which might play an important role in the development of pterygium. The DEGs enriched in the pathway of Focal adhesion included JUN, COL4A2 (collagen type IV alpha 2, Gene ID: 1284), ACTN1 (actinin alpha 1, Gene ID: 87), FN1, RAC3, LAMB1, TNN (tenascin N, Gene ID: 63923) and COL1A1 (collagen type I alpha 1 chain, Gene ID: 1277). These genes were identified as candidate genes for further study.
Brain Environment Interactions: Stress, Posttraumatic Stress Disorder, and the Need for a Postmortem Brain Collection
Published in Psychiatry, 2022
Elizabeth Osuch, Robert Ursano, He Li, Maree Webster, Chris Hough, Carol Fullerton, Gregory Leskin
In recent years, advances in our understanding of genetics and gene expression have created increased interest in and knowledge of the interaction of our environment, including developmental factors, with our biology. In the fields of psychiatry and psychology, this topic has long been a focus, usually in the form of the age -old question of the balance of “nature” and “nurture” in the determination of behavior. At the same time that researchers are investigating candidate genes for mental illnesses such as bipolar disorder, autism and schizophrenia, studies are demonstrating that environmental influences across the various stages of an animal or human’s life have significant effects on behavior and brain physiology. Recent studies have helped to overcome the dichotomy between genetic and environmental influences by demonstrating that environmental events alter gene expression—whether a gene is turned on or off—thereby changing the physiology of neurons, synapses and hence neuronal networks, leading to alterations in behavior. In other words, we now know that the environment can influence behavior through changes in gene expression.