Diabetic Retinopathy
Diabetic retinopathy (DR) is a serious microvascular complication of diabetes, characterized by progressive damage to the blood vessels in the retina, the light-sensitive tissue at the back of the eye. It is a leading cause of vision impairment and blindness among working-age adults globally.
The biological basis of diabetic retinopathy involves prolonged exposure to high blood glucose levels, which can damage the delicate blood vessels in the retina. This damage leads to various pathological changes, including microaneurysms, hemorrhages, exudates, and eventually neovascularization (growth of abnormal new blood vessels) and fibrosis, which can cause retinal detachment. While glycemic control and duration of diabetes are significant contributors to the development and progression of DR, these factors do not fully account for individual susceptibility . Furthermore, the selection of control groups can introduce bias; for instance, including individuals with other diabetic complications like diabetic nephropathy in control cohorts can dilute the statistical power to identify genetic loci specific to DR or to differentiate shared genetic predispositions between these complications[1]. The consistency of findings across different studies is also a concern, as evidenced by significant heterogeneity in effect sizes between cohorts, which can complicate the replication and generalizability of identified genetic variants [2].
Phenotypic Heterogeneity and Generalizability Across Populations
Section titled “Phenotypic Heterogeneity and Generalizability Across Populations”The varied approaches to defining and measuring diabetic retinopathy present a notable limitation. Diagnostic variations among ophthalmologists can lead to minor misclassification biases, affecting the accuracy of case ascertainment[1]. Moreover, broad definitions of DR, such as classifying “any DR” against “no DR,” might overlook genetic variants specifically associated with disease progression or severe forms. More granular phenotyping, including studies focusing on advanced stages of DR or comparing cases with specific clinical characteristics like shorter diabetes duration with good glycemic control, is recognized as essential for uncovering more precise genetic associations[1]. Additionally, many genetic studies have focused on specific ethnic populations, such as Japanese, Chinese, or African American cohorts [3]. While multi-ethnic studies are emerging, findings from one population may not be fully generalizable due to differences in genetic backgrounds and environmental exposures, necessitating broader and more diverse investigations [4].
Complex Etiology and Unaccounted Environmental Factors
Section titled “Complex Etiology and Unaccounted Environmental Factors”Despite evidence for the heritability of diabetic retinopathy severity[5], a substantial portion of the disease’s genetic risk remains unexplained, contributing to the phenomenon of “missing heritability.” Clinical risk factors such as glycated hemoglobin and the duration of diabetes, while crucial, only account for a small percentage of the variation in retinopathy risk (e.g., 11%)[6]. This suggests that numerous other genetic factors, environmental influences, and their complex interactions are yet to be fully elucidated. Comprehensive understanding requires further investigation into how genetic predispositions interact with diverse environmental exposures, lifestyle factors, and other unmeasured confounders to influence DR susceptibility and progression. Bridging these remaining knowledge gaps necessitates integrated research that combines detailed genetic and extensive environmental data[7].
The genetic landscape of diabetic retinopathy (DR) is complex, involving numerous genes and variants that modulate risk through various biological pathways, from glucose metabolism to immune response and cellular stress. Understanding these genetic factors provides insights into disease susceptibility and progression.
Variants in genes centrally involved in type 2 diabetes (T2D) pathogenesis are key contributors to diabetic retinopathy. TheTCF7L2gene, a critical transcription factor in the Wnt signaling pathway, is essential for glucose homeostasis and pancreatic beta-cell function. Variants such asrs7903146 and rs34872471 in TCF7L2are well-established risk factors for T2D, with research also indicating their association with the progression of retinopathy[8]. This gene is also linked to processes like proinsulin conversion in various populations[9]. Similarly, CDKAL1 (rs9348441 ), involved in tRNA modification and beta-cell insulin secretion, andIGF2BP2 (rs7630554 , rs9859406 , rs11711477 ), an RNA-binding protein affecting cell growth and metabolism, contribute significantly to T2D susceptibility, thereby increasing the risk for microvascular complications like DR. KCNQ1 (rs2237897 , rs234864 ), which encodes a potassium channel crucial for insulin release, further highlights the genetic architecture linking impaired glucose regulation to retinopathy development, a common focus of genome-wide association studies[10]. These variants collectively underscore how genetic predisposition to T2D can profoundly influence the risk and severity of diabetic retinopathy.
Other genetic variants contribute to diabetic retinopathy by influencing broader metabolic and cellular stress pathways. TheFTO gene, with variant rs1421085 , is primarily known for its strong association with obesity and body mass index, which are significant risk factors for developing type 2 diabetes and, subsequently, diabetic retinopathy.WFS1(Wolframin ER Membrane Glycoprotein), with variants likers1801214 and rs9457 , plays a vital role in endoplasmic reticulum (ER) stress response and beta-cell survival; its dysfunction is linked to diabetes and optic atrophy, suggesting a direct impact on retinal health. Furthermore,CDKN2B-AS1 (rs10811661 ), a long non-coding RNA, regulates cell cycle and senescence genes, and its variants are associated with T2D and vascular diseases, which could exacerbate retinal damage in a diabetic context [11]. These genes collectively highlight how diverse biological mechanisms, from energy balance to cellular stress and proliferation, can influence an individual’s susceptibility to diabetic retinopathy as explored in multiethnic GWAS[6].
Immune system components and non-coding RNA elements also play a role in the complex etiology of diabetic retinopathy. TheHLA-DQB1 gene, involved in immune recognition and antigen presentation, has the variant rs9274619 , which is often associated with autoimmune conditions, including type 1 diabetes. Although primarily known for autoimmune links, immune dysregulation and chronic inflammation are increasingly recognized as key drivers in the progression of both type 1 and type 2 diabetic retinopathy[12]. Nearby, the intergenic variant rs9274830 , located between HLA-DQB1 and the pseudogene MTCO3P1, may also influence immune responses or regulatory elements affecting adjacent genes. Additionally, the intergenic variant rs4933736 , located near EXOC6 and potentially associated with Y_RNAfunction, could impact cellular trafficking or stress responses, which are relevant to the intricate processes of retinal endothelial cell function and neurovascular integrity. The identification of such loci underscores the multifactorial nature of diabetic retinopathy, encompassing not only metabolic but also inflammatory and cellular regulatory pathways[3].
Understanding Diabetic Retinopathy: Definition and Key Terminology
Section titled “Understanding Diabetic Retinopathy: Definition and Key Terminology”Diabetic retinopathy (DR) is precisely defined as a chronic, progressive, and potentially sight-threatening disease affecting the retinal microvasculature, with its pathophysiological changes intensified by the presence of diabetes[13]. It represents the most common eye complication among individuals with diabetes and is a leading cause of blindness among the working-age population [13]. Key terminology associated with this condition includes non-proliferative diabetic retinopathy (NPDR), proliferative diabetic retinopathy (PDR), and diabetic macular edema (DME), which represent distinct stages and manifestations of the disease. Research indicates that DR is a heritable trait in both type 1 and type 2 diabetes, with a more significant genetic component observed in its more severe forms[13].
Classification Systems and Severity Grading
Section titled “Classification Systems and Severity Grading”Diabetic retinopathy is broadly classified into two main categories: non-proliferative diabetic retinopathy (NPDR) and proliferative diabetic retinopathy (PDR), distinguished primarily by the absence or presence of abnormal new blood vessel growth on the retina[13]. NPDR represents earlier stages characterized by microaneurysms, hemorrhages, and exudates, while PDR signifies advanced disease where new, fragile vessels can lead to severe vision loss through hemorrhage or retinal detachment[13]. Diabetic macular edema (DME), a distinct and critical complication, involves fluid accumulation in the macula, the central part of the retina responsible for sharp, detailed vision, and can occur at any stage of DR[14]. Standardized classification systems, such as the modified Airlie House classification, as extended by the Early Treatment Diabetic Retinopathy Study (ETDRS), utilize stereoscopic color fundus photographs to grade the severity of DR, ensuring consistent assessment across clinical and research settings[15].
Diagnostic Criteria and Measurement Approaches
Section titled “Diagnostic Criteria and Measurement Approaches”The diagnosis and assessment of diabetic retinopathy rely on specific clinical criteria and measurement approaches, often beginning with routine retinal screening[13]. A primary measurement approach involves the examination of stereoscopic color fundus photographs, which allows for detailed visualization and grading of retinal changes [15]. Clinical criteria for classification, such as distinguishing NPDR from PDR, are based on the presence or absence of abnormal new vessels [13]. Furthermore, several factors are consistently associated with the prevalence and risk of DR, including the duration of diabetes, glycemic control as measured by HbA1c, blood pressure, lipid levels, and obesity[16] [17] [4]. These criteria and associated risk factors are crucial for both diagnostic confirmation and for understanding the progression and management of the condition.
Manifestations and Progression of Retinopathy
Section titled “Manifestations and Progression of Retinopathy”Diabetic retinopathy (DR) presents a spectrum of ocular manifestations, often progressing silently in its early stages before significant vision impairment occurs. The overall prevalence of any retinopathy among individuals with diabetes is reported to be 40.3%[14], highlighting its common occurrence. The disease typically begins as non-proliferative diabetic retinopathy (NPDR), characterized by microaneurysms, hemorrhages, and cotton wool spots, which may not initially affect vision. However, the progression to proliferative diabetic retinopathy (PDR) involves the growth of new, abnormal blood vessels on the retina or optic disc, which are fragile and prone to bleeding, potentially leading to severe vision loss or retinal detachment[14]. A critical complication, diabetic macular edema (DME), involves swelling of the macula, the central part of the retina responsible for detailed vision, and is prevalent in 8.2% of diabetic patients[14], directly impacting central visual acuity[14].
Diagnostic Assessment and Severity Staging
Section titled “Diagnostic Assessment and Severity Staging”The diagnosis and staging of diabetic retinopathy primarily rely on comprehensive ophthalmic examinations, which allow for the identification of characteristic retinal changes. These clinical assessments help classify the severity of DR, ranging from mild NPDR to severe PDR and DME[14]. Beyond direct observation, epidemiological studies are crucial tools for identifying risk factors and developing effective preventive strategies, while genetic studies contribute to understanding the underlying biological mechanisms and identifying specific genetic pathways involved in DR progression [13]. Genome-wide association studies (GWAS) have been employed to identify loci associated with DR, often considering factors like duration of diabetes and glycemic control, measured by biomarkers such as hemoglobin A1c[4]. The severity of DR is a heritable trait, with a greater genetic component observed in more severe forms of the disease[5].
Heterogeneity and Prognostic Indicators
Section titled “Heterogeneity and Prognostic Indicators”Diabetic retinopathy exhibits significant variability across individuals, influenced by a complex interplay of genetic and environmental factors. Heritability of DR severity has been confirmed through both twin and family studies in individuals with type 1 and type 2 diabetes[13]. Inter-individual differences also manifest in age-related changes and ethnic variations, with genetic studies often conducted across ancestrally diverse populations to capture this phenotypic diversity [4]. The identification of genetic factors associated with DR is diagnostically significant, as it can assist in predicting individual risk, guiding clinical prevention strategies, and suggesting potential molecular targets for pharmacological interventions [13]. Furthermore, DR may share genetic bases or co-regulation with other complex traits, including type 2 diabetes and kidney disease, indicating broader systemic implications[8].
Diagnosis
Section titled “Diagnosis”Diabetic retinopathy (DR) is a progressive microvascular complication of diabetes that necessitates a multi-faceted diagnostic approach, primarily focusing on ophthalmological assessment, complemented by genetic insights. It is characterized by pathophysiological changes in the retinal microvasculature and is the most common eye complication in diabetic patients, often leading to blindness . The duration of diabetes and the degree of glycemic control are significant risk factors, highlighting the central role of glucose dysregulation in driving the disease[4].
Genetic Predisposition and Regulatory Networks
Section titled “Genetic Predisposition and Regulatory Networks”Diabetic retinopathy is a complex condition influenced by both environmental factors, such as glycemic control, and a significant genetic component, with studies confirming its heritable nature in both type 1 and type 2 diabetes[13]. Genetic studies are essential for uncovering the underlying biological mechanisms and pathways that contribute to an individual’s susceptibility [13]. This genetic predisposition often manifests as a greater component in more severe forms of the disease[13]. Genome-wide association studies (GWAS) have identified specific genetic loci and regulatory elements associated with diabetic retinopathy. For instance, research has suggested a potential association with a long intergenic non-coding RNA (lncRNA), indicating that non-coding regions of the genome can play a regulatory role in disease development[3]. Additionally, variants in genes like Complement Factor H (CFH) and Complement Factor B (CFB) have been linked to retinopathy in type 2 diabetic patients, implicating immune and inflammatory regulatory networks in its pathogenesis[18]. The impact of common genetic determinants of hemoglobin A1c on type 2 diabetes risk also points to a shared genetic basis influencing both diabetes and its vascular outcomes[19].
Molecular Pathways and Vascular Damage
Section titled “Molecular Pathways and Vascular Damage”The progression of diabetic retinopathy involves several critical molecular and cellular pathways that lead to microvascular damage. One such pathway involves oxidative stress, where the NADPH Oxidase 4 (NOX4) gene has been associated with severe diabetic retinopathy in type 2 diabetes[13]. NOX4 is a key enzyme in the production of reactive oxygen species, which contribute to cellular damage and inflammation in the retina. Abnormalities in Wnt signaling, a crucial pathway for cell proliferation, differentiation, and angiogenesis, are also implicated as underlying mechanisms leading to susceptibility to multiple ocular diseases, including diabetic retinopathy[20]. Furthermore, inflammatory responses play a significant role in vascular pathology. Patients with diabetic retinopathy exhibit altered L-selectin expression in lymphocytes and increased adhesion to the endothelium, suggesting a heightened inflammatory state that contributes to vascular dysfunction[21]. The complement system, involving biomolecules like CFH and CFB, is also activated, further exacerbating inflammation and contributing to the breakdown of the blood-retinal barrier and subsequent vascular leakage and neovascularization. These molecular dysregulations collectively contribute to the characteristic changes observed in the retinal microvasculature, including pericyte loss, endothelial cell dysfunction, and abnormal vessel growth.
Systemic Consequences and Pleiotropic Mechanisms
Section titled “Systemic Consequences and Pleiotropic Mechanisms”Diabetic retinopathy is not an isolated ocular condition but often reflects broader systemic consequences of diabetes, particularly affecting the microvasculature. The genetic architecture underlying type 2 diabetes (T2D) shares common risk loci with other complex traits and vascular outcomes, suggesting pleiotropic mechanisms where certain genetic variants influence multiple related conditions[8]. This shared genetic basis is evident in the overlap between diabetic retinopathy and other microvascular complications, such as diabetic nephropathy, where susceptibility loci for kidney disease in type 1 diabetes have been identified[22]. The connection between these conditions highlights that the chronic hyperglycemia and associated metabolic dysregulation impact various organ systems, leading to similar patterns of vascular damage. For example, a variant within the FTO gene, known for its association with obesity and type 2 diabetes, also confers susceptibility to diabetic nephropathy in Japanese patients, further illustrating these systemic and pleiotropic links[23]. Identifying these shared genetic determinants and biological pathways provides insights into the systemic nature of diabetic complications and offers potential avenues for therapeutic strategies targeting common mechanisms across different affected organs.
Pathways and Mechanisms
Section titled “Pathways and Mechanisms”Metabolic Dysregulation and Oxidative Stress
Section titled “Metabolic Dysregulation and Oxidative Stress”High glucose metabolism is a fundamental underlying mechanism contributing to the susceptibility of various ocular diseases, including diabetic retinopathy[20]. This dysregulation impacts energy metabolism within retinal cells, leading to cellular stress and damage. The NADPH Oxidase 4 (NOX4) gene is associated with severe diabetic retinopathy in type 2 diabetes[13]. NOX4’s involvement suggests that increased oxidative stress, mediated by reactive oxygen species production, plays a critical role in the pathogenesis of the disease, representing a key pathway dysregulation in the diabetic retinal environment.
Cellular Signaling and Developmental Pathways
Section titled “Cellular Signaling and Developmental Pathways”Abnormalities in critical signaling pathways, such as Wnt signaling, are identified as underlying mechanisms leading to susceptibility to multiple ocular diseases, including diabetic retinopathy[20]. This pathway is crucial for proper retinal development and its dysregulation can contribute to the pathological changes observed in the retina. Such disruptions in developmental processes, modulated by intricate intracellular signaling cascades and receptor activation, highlight how impaired regulatory mechanisms can lead to the structural and functional deterioration characteristic of diabetic retinopathy.
Genetic and Transcriptional Regulatory Mechanisms
Section titled “Genetic and Transcriptional Regulatory Mechanisms”Genetic factors play a significant role in determining an individual’s susceptibility to diabetic retinopathy. Studies have identified a potential association between diabetic retinopathy and a long intergenic non-coding RNA (lincRNA) in a Japanese population[3]. LincRNAs are involved in gene regulation, suggesting that their dysregulation could alter gene expression patterns critical for retinal health. Furthermore, common genetic determinants of hemoglobin A1c impact type 2 diabetes risk, which in turn influences the metabolic environment and susceptibility to diabetic retinopathy[4].
Inter-Pathway Crosstalk and Pleiotropic Effects
Section titled “Inter-Pathway Crosstalk and Pleiotropic Effects”Diabetic retinopathy often reflects a broader systems-level integration of metabolic and genetic factors. There is evidence of possible co-regulation or a shared genetic basis between type 2 diabetes and other complex traits, including vascular outcomes and diabetic nephropathy[8]. This indicates significant pathway crosstalk and network interactions, where dysregulation in one system, such as glucose metabolism, can have pleiotropic effects across multiple organs. The shared genetic susceptibility highlights a hierarchical regulation where overarching genetic predispositions influence the emergence of multiple diabetes-related complications.
Population Studies
Section titled “Population Studies”Diabetic retinopathy (DR) is a significant microvascular complication of diabetes, with its prevalence and associated risk factors extensively studied across diverse populations. Global epidemiological studies have established its widespread impact, identifying key demographic and clinical correlates. For instance, a comprehensive review highlighted the global prevalence and major risk factors for diabetic retinopathy[24], underscoring the disease’s substantial public health burden. In the United States, research has detailed the prevalence of DR among adults[25], while in Australia, studies have investigated the prevalence and factors associated with DR within the Australian population [26]. Longitudinal studies, such as the Wisconsin Epidemiologic Study of Diabetic Retinopathy, have been instrumental in characterizing the prevalence and risk of DR over time, noting factors like age at diagnosis[27]. These large-scale investigations consistently point to the duration of diabetes and glycemic control as critical determinants of DR development and progression [4].
Genetic predisposition plays a crucial role in the development and severity of diabetic retinopathy, with numerous genome-wide association studies (GWAS) identifying population-specific and multiethnic loci. Heritability studies, such as the Family Investigation of Nephropathy and Diabetes (FIND-Eye) study, have demonstrated the inherited nature of DR severity[5], with further research confirming the heritability of proliferative diabetic retinopathy[28]. Cross-population comparisons reveal distinct genetic landscapes; for example, GWAS conducted in a Japanese population identified potential associations with a long intergenic non-coding RNA [3], while a separate GWAS in a Chinese population also sought to uncover genetic links to diabetic retinopathy[6]. Furthermore, multiethnic GWAS efforts have investigated genetic determinants of DR, considering factors like diabetes duration and glycemic control [4]. These studies have expanded to include African populations, with a GWAS for proliferative diabetic retinopathy in Africans identifying specific loci[29], highlighting the importance of diverse cohorts in understanding the genetic architecture of the disease. A meta-analysis in Caucasian patients with type 2 diabetes identified an association between the NADPH Oxidase 4 (NOX4) gene and severe diabetic retinopathy, integrating data from multiple European and Australian cohorts[13].
Population studies on diabetic retinopathy frequently leverage large-scale cohorts and advanced methodologies to understand its complex etiology. Key cohorts contributing to this understanding include the Wisconsin Epidemiologic Study of Diabetic Retinopathy, the Blue Mountains Eye Study, the Cardiovascular Health Study, and the Atherosclerosis Risk in Communities (ARIC) study, which have provided insights into prevalence, risk factors, and the association of DR with broader cardiovascular health[27]. Other significant cohorts involved in genetic investigations include the Lifelines Cohort Study, the Scania Diabetes Registry, the Australian DR Genetics Case-Control Study, the Finnish Diabetic Nephropathy Study, and the Genetics of Kidneys in Diabetes study/Epidemiology of Diabetes Interventions and Complications [4]. Methodologically, studies often employ GWAS to search for novel susceptibility loci, alongside liability threshold modeling to account for complex traits influenced by disease duration and glycemic control[4]. The use of meta-analyses across multiple cohorts, often involving thousands of participants, enhances statistical power and generalizability of findings, though careful consideration of varying diagnostic criteria for DR across studies is crucial for accurate synthesis [13]. These diverse study designs, from longitudinal observational studies to multi-ancestry genetic analyses, collectively contribute to a comprehensive population-level understanding of diabetic retinopathy.
Key Variants
Section titled “Key Variants”| RS ID | Gene | Related Traits |
|---|---|---|
| rs7903146 rs34872471 | TCF7L2 | insulin measurement clinical laboratory measurement, glucose measurement body mass index type 2 diabetes mellitus type 2 diabetes mellitus, metabolic syndrome |
| rs1421085 | FTO | body mass index obesity energy intake pulse pressure measurement lean body mass |
| rs7630554 rs9859406 rs11711477 | IGF2BP2 | thyroid stimulating hormone amount Drugs used in diabetes use measurement diabetes mellitus, Drugs used in diabetes use measurement type 2 diabetes mellitus diabetic retinopathy |
| rs10811661 | CDKN2B-AS1 | type 2 diabetes mellitus blood glucose amount blood glucose amount, body mass index body mass index HbA1c measurement |
| rs9274619 | HLA-DQB1 | diabetic retinopathy actinic keratosis |
| rs1801214 rs9457 | WFS1 | type 2 diabetes mellitus life span trait diabetic neuropathy type 2 diabetes nephropathy diabetic polyneuropathy |
| rs2237897 rs234864 | KCNQ1 | type 2 diabetes mellitus disposition index measurement, glucose homeostasis trait body mass index body weight type 1 diabetes mellitus |
| rs4933736 | Y_RNA - EXOC6 | type 2 diabetes nephropathy diabetic retinopathy HbA1c measurement |
| rs9274830 | HLA-DQB1 - MTCO3P1 | diabetic retinopathy |
| rs9348441 | CDKAL1 | glucose measurement HbA1c measurement type 2 diabetes mellitus gestational diabetes diabetes mellitus, Drugs used in diabetes use measurement |
Frequently Asked Questions About Diabetic Retinopathy
Section titled “Frequently Asked Questions About Diabetic Retinopathy”These questions address the most important and specific aspects of diabetic retinopathy based on current genetic research.
1. My parents have DR; am I definitely going to get it too?
Section titled “1. My parents have DR; am I definitely going to get it too?”Not necessarily, but your risk is higher. Research shows that the severity of diabetic retinopathy has a strong heritable component, meaning genetic factors passed down in families play a role. However, it’s not a simple “yes or no” inheritance; managing your diabetes well and having regular eye exams are crucial protective steps.
2. I manage my blood sugar well, but still worry about DR. Why?
Section titled “2. I manage my blood sugar well, but still worry about DR. Why?”Even with excellent glycemic control, some individuals are more susceptible due to their genetics. While high blood sugar is a major factor, genetic variants can influence how your retinal blood vessels respond to diabetes, increasing your risk regardless of how well you manage your glucose levels. This highlights the complex interplay between your genes and lifestyle.
3. Does my ethnic background make me more prone to DR?
Section titled “3. Does my ethnic background make me more prone to DR?”Yes, your ethnic background can influence your risk. Genetic studies have identified specific risk factors and loci associated with diabetic retinopathy in various populations, including Japanese, Chinese, and African individuals. While multiethnic studies are emerging, findings from one group may not fully apply to another, showing genetic differences can play a role.
4. Can a DNA test predict if I’ll get severe DR?
Section titled “4. Can a DNA test predict if I’ll get severe DR?”Currently, a DNA test can’t definitively predict severe DR, but genetic research is moving in that direction. Scientists are identifying specific genetic markers, like variations near the GRB2 gene or in NOX4, that are associated with increased risk or severity. The goal is to develop personalized risk assessments, but more research is needed for widespread clinical use.
5. Why does my DR seem to progress faster than my friend’s?
Section titled “5. Why does my DR seem to progress faster than my friend’s?”The rate of DR progression can be influenced by individual genetic differences. Beyond factors like blood sugar control and diabetes duration, your unique genetic makeup can affect how quickly your retinal blood vessels are damaged and how the disease advances. This explains why people with similar diabetes management might experience different disease courses.
6. If I control my diabetes perfectly, can I still get DR?
Section titled “6. If I control my diabetes perfectly, can I still get DR?”Unfortunately, yes, it’s possible. While excellent blood glucose control is the most important step to reduce your risk, it doesn’t eliminate it entirely. Genetic predisposition plays a significant role in individual susceptibility, meaning some people are genetically more vulnerable to retinal damage even with diligent diabetes management.
7. My family has no DR history, but I got it. How?
Section titled “7. My family has no DR history, but I got it. How?”This points to the complex nature of DR, where not all genetic risk is easily visible in family history. New genetic variants can arise, or you might have a combination of common genetic factors that, when combined with your personal diabetes experience, increase your susceptibility even without a strong family pattern. Environmental factors also play a part.
8. Do my daily habits affect my genetic risk for DR?
Section titled “8. Do my daily habits affect my genetic risk for DR?”Your daily habits don’t change your underlying genetic code, but they profoundly influence how your genes express themselves and interact with your environment. While you can’t alter your inherited risk factors, aggressive management of blood glucose, blood pressure, and lipids through lifestyle choices can significantly reduce theimpact of those genetic predispositions.
9. Why do some diabetics get DR and others don’t, even with similar sugar levels?
Section titled “9. Why do some diabetics get DR and others don’t, even with similar sugar levels?”This difference often comes down to individual genetic susceptibility. Even with comparable diabetes duration and glycemic control, certain genetic variants can make some people’s retinal blood vessels more vulnerable to damage from high blood sugar, while others are more resilient. This “missing heritability” is a key area of ongoing research.
10. Does having diabetes for a long time guarantee I’ll get DR?
Section titled “10. Does having diabetes for a long time guarantee I’ll get DR?”No, not necessarily. While the duration of diabetes is a significant risk factor, it doesn’t guarantee you’ll develop DR. Your genetic makeup plays a crucial role in determining your individual susceptibility. Some people with long-standing diabetes may never develop severe DR, thanks in part to protective genetic factors, while others develop it sooner.
This FAQ was automatically generated based on current genetic research and may be updated as new information becomes available.
Disclaimer: This information is for educational purposes only and should not be used as a substitute for professional medical advice. Always consult with a healthcare provider for personalized medical guidance.
References
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