Fever
Introduction
Fever, also known as pyrexia, is a common physiological response characterized by an elevation in body temperature above the normal range. It is not an illness itself but rather a symptom, often indicating the body's immune system is actively fighting off an infection or inflammation. This adaptive response is regulated by the hypothalamus, which resets the body's temperature set point in response to pyrogens—substances that induce fever.
Biological Basis
At a biological level, fever is initiated when pyrogens, either exogenous (from pathogens like bacteria or viruses) or endogenous (produced by the body's immune cells), signal the hypothalamus. This leads to a cascade of events, including the production of prostaglandins, which then act on the hypothalamus to raise the set point. The body responds by increasing heat production (e.g., shivering) and decreasing heat loss (e.g., vasoconstriction) to reach the new, higher temperature. This elevated temperature can inhibit the growth of certain pathogens and enhance immune cell function.
Clinical Relevance
Fever is a crucial clinical sign, guiding diagnosis and treatment across a wide spectrum of diseases. Genetic studies have begun to unravel the host determinants influencing susceptibility and outcome for various fever-related conditions. For instance, variation at the HLA-DRB1 gene is associated with resistance to enteric fever, a systemic infection caused by Salmonella enterica serovar Typhi or Paratyphi. [1] A strong association for enteric fever has been mapped to rs7765379 in the class II human leukocyte antigen (HLA) region, near the HLA-DQB1 and HLA-DRB1 genes, with the minor allele being under-represented in cases. [1] The classical HLA-DRB1*04:05 allele also shows a significant association. [1]
Beyond bacterial infections, genome-wide association studies (GWAS) have identified human genetic variants linked to the fatal outcome of Lassa fever. [2] In other infectious contexts, a GWAS identified an association between scarlet fever and the HLA-DQB1 gene in the class II region, specifically with the amino acid polymorphism HLA-DQB1 Gly45 (rs36205178). [3] Genetic factors also play a role in allergic diseases, where hay fever, an allergic reaction with symptoms that can sometimes be confused with infectious fevers, shares a genetic origin with asthma and eczema. [4] The HLA region, in general, contains susceptibility loci for multiple common infections. [3]
Social Importance
The prevalence of fever as a symptom across a vast array of illnesses makes it a condition of significant public health and social importance. It is a leading reason for medical consultations, affecting individuals of all ages and impacting daily life, work, and education. Understanding the genetic underpinnings of susceptibility and response to different types of fever-inducing conditions, including infectious diseases and allergic reactions, can lead to improved diagnostics, personalized treatments, and public health strategies, particularly in regions where specific infectious fevers are endemic.
Methodological and Statistical Considerations
The interpretation of genetic associations for fever is influenced by various methodological and statistical constraints. Insufficient sample sizes in some studies limit statistical power, potentially leading to a failure to replicate findings or detect modest genetic effects, as observed in meningitis susceptibility studies with smaller cohorts . Similarly, the rs77344822 variant, associated with OTUD7A (OUT deubiquitinase 7A), impacts an enzyme critical for regulating protein ubiquitination, a process fundamental to various immune signaling pathways and cellular stress responses. Changes in OTUD7A activity due to this variant may modify the intensity or duration of inflammatory signals, directly influencing fever development. The rs28360654 variant associated with PDE10A (Phosphodiesterase 10A) affects an enzyme that breaks down cyclic nucleotides, vital secondary messengers in immune cell activation and cytokine production. Altered PDE10A function could disrupt these signaling cascades, affecting the regulation of inflammation and the febrile state. [2] Furthermore, the rs79301185 variant, located near ADRA1A (Alpha-1A adrenergic receptor) and MIR548H4, relates to thermoregulation. ADRA1A mediates vasoconstriction, a critical mechanism the body uses to conserve heat and raise core temperature during fever. This variant could influence ADRA1A expression or receptor sensitivity, thereby impacting the body's ability to generate and maintain fever.
Other variants affect genes involved in fundamental cellular processes and non-coding RNA regulation, which indirectly but significantly shape the immune response. For instance, rs144384547 is found within the region of RNA5SP224 and RNA5SP225, which encode small RNA components essential for cellular machinery and gene expression. Genetic variations here might subtly alter ribosomal RNA processing or other non-coding RNA functions, subsequently affecting cellular responses to pathogens or inflammatory stimuli that trigger fever. Long intergenic non-coding RNAs (lncRNAs), such as LINC00358 and LINC01075, play diverse roles in gene expression regulation and immune cell differentiation. The rs192688594 variant in this lncRNA region could modify their regulatory capacity, potentially altering the genetic programs that control inflammatory responses and the onset or resolution of fever. [5] Meanwhile, the rs200973787 variant associated with CDC14A (Cell Division Cycle 14A) affects a phosphatase enzyme crucial for cell cycle progression and mitotic exit, processes vital for immune cell proliferation and tissue repair during infection. A variation in CDC14A could therefore influence the immune system's capacity to respond effectively, impacting the intensity and duration of a fever. [6]
Finally, some variants are linked to genes with broader physiological impacts, including neuromodulation and circadian rhythms, which are intimately connected to fever. The rs17181171 variant, associated with OPRM1 (Opioid Receptor Mu 1), is significant because this receptor not only mediates pain but also influences immune modulation and thermoregulation in the central nervous system. This variant could modify receptor sensitivity or expression, affecting how the body perceives illness, modulates inflammation, and regulates temperature during a febrile state. The locus containing TPTEP2-CSNK1E and KCNJ4 is another example, with the rs397822879 variant. CSNK1E (Casein Kinase 1 Epsilon) is involved in regulating circadian rhythms and various signaling pathways that affect inflammatory responses. [3] KCNJ4 (Potassium Inwardly Rectifying Channel Subfamily J Member 4) encodes a potassium channel essential for cellular excitability, impacting neuronal function and immune cell activity. Therefore, this variant could influence both the neural control of thermoregulation and the inflammatory cascade, contributing to individual differences in fever response and associated symptoms. [2]
Operational Definition and Measurement Criteria
Fever, as a clinical sign, is precisely defined by an elevated body temperature exceeding a specific threshold. In clinical and research settings, fever is often operationally defined by a temperature on admission greater than 37.8 degrees Celsius. [2] This objective measurement serves as a critical diagnostic criterion, allowing for consistent identification across different patient populations and studies. The quantitative nature of this definition facilitates standardized data collection and analysis, which is essential for genetic association studies and epidemiological tracking of disease prevalence. Such a clear cut-off value is vital for distinguishing a febrile state from normal physiological variations in body temperature.
Clinical Classifications and Diagnostic Frameworks
Fever manifests across a spectrum of diseases, leading to specific clinical classifications based on etiology and presentation. For instance, "enteric fever" is a distinct disease characterized by clinical signs and symptoms, and definitively diagnosed by the culture-confirmation of Salmonella Typhi or Salmonella Paratyphi A in blood or bone marrow samples . Beyond the major histocompatibility complex, other genes like MICB and PLCE1, as well as variations in the vitamin D receptor (VDR) and Fc gamma receptor IIa (FCGR2A) genes, have been linked to susceptibility to dengue shock syndrome, a severe form of dengue fever. [6] Furthermore, rare genetic diseases, such as those caused by mutations in the interleukin (IL)-12 or interferon (IFN)-γ pathways, can lead to hypersusceptibility to intracellular bacteria like non-typhoidal Salmonella, which can result in fever. [1] For allergic conditions like hay fever, there is a shared genetic origin with asthma and eczema, with numerous genetic variants contributing to a polygenic risk for these inflammatory responses. [4]
Immune System Modulation and Host-Pathogen Interactions
Genetic variations often exert their influence on fever susceptibility by modulating the immune system's ability to recognize and respond to pathogens or allergens. The human leukocyte antigen (HLA) region, critical for antigen presentation, contains genes whose specific amino acid polymorphisms in the peptide-binding cleft are associated with resistance or susceptibility to various infections. [3] For example, specific HLA-DRB1 alleles can confer resistance to enteric fever by influencing how immune cells present bacterial antigens, thereby shaping the adaptive immune response. [1] Similarly, variations in HLA-DQB1 and HLA-B impact the host's response to streptococcal infections and pneumonia, respectively, underscoring the vital role of these genes in pathogen recognition and immune defense. [3] The intricate interface between the human host and the pathogen, dictated by these genetic determinants, is crucial in dictating the outcome of infectious diseases that typically present with fever. [1]
Environmental Influences, Early Life, and Epigenetic Regulation
Environmental factors interact with genetic predispositions to influence the development of fever-associated conditions, with early life exposures and epigenetic modifications playing a significant role. Environmental risk factors can modulate DNA CpG methylation, which in turn affects gene expression and contributes to the etiology of conditions such as allergic diseases like hay fever. [4] These epigenetic changes, potentially influenced by early life exposures, can alter gene activity without changing the underlying DNA sequence, impacting immune function and inflammatory responses throughout an individual's life. Studies incorporating age-of-onset information for allergic diseases suggest that early life influences are genetically correlated with disease susceptibility, indicating a developmental component to the manifestation of these conditions. [5] Furthermore, broad epidemiological factors, encompassing various environmental exposures and socioeconomic conditions, are recognized to influence the incidence and severity of infectious diseases, such as dengue shock syndrome, which is characterized by fever. [6]
Co-occurring Conditions and Disease Progression
The presence of other health conditions and the overall physiological state of an individual can significantly impact the likelihood, severity, and outcome of fever. Clinical and laboratory predictors are recognized to influence the outcome of severe febrile illnesses, such as Lassa fever. [2] For complex, often fever-associated conditions like allergic diseases (asthma, hay fever, eczema), studies indicate a strong genetic influence on disease risk, with the clustering of multiple risk factors suggesting an overlap in causal genes and pathways. [7] This genetic interconnectedness implies that comorbidities can share underlying biological mechanisms, potentially exacerbating the inflammatory responses that lead to fever. While specific medication effects or age-related changes are not extensively detailed for fever itself within the provided context, the progression and severity of diseases that cause fever are undeniably influenced by the individual's overall health status and existing conditions. [6]
Immune Response and Molecular Signaling
The body's immune system plays a crucial role in the manifestation and outcome of various fever conditions, involving intricate molecular and cellular pathways. For instance, severe dengue infections, characterized by dengue shock syndrome, are influenced by an early whole-blood transcriptional signature, virus burden, and the degree of immune activation. [6] Similarly, resistance to enteric fever, caused by Salmonella Typhi, is significantly mediated by the human host's interaction with the pathogen, with rare genetic conditions affecting IL-12 or IFN-γ pathways leading to hypersusceptibility to intracellular bacteria. [1] The NKG2D receptor, which assembles with signaling dimers into a hexameric structure in the membrane, represents a key biomolecule involved in immune recognition, and its components are implicated in susceptibility to dengue shock syndrome. [6]
Further illustrating the complexity of immune regulation, the glycosphingolipid (GSL) biosynthesis pathway is a significant molecular pathway involved in host-pathogen interactions and cell-cell recognition. [3] Genes like ABO and FUT2, which determine the secretion of ABO blood group antigens into body fluids, are part of this pathway and show genetic variation influencing susceptibility to infections. [3] In allergic fevers, such as hay fever, the immune response involves peripheral blood activation that can affect multiple organs, including the lungs, leading to inflammation, as seen when mutations in the FLG gene impair skin barrier function and increase sensitivity to external allergens. [7] This indicates a systemic consequence driven by specific immune cell activities and signaling pathways.
Genetic Basis of Fever Susceptibility
Genetic mechanisms are fundamental in determining an individual's susceptibility and response to different types of fever. Genome-wide association studies (GWAS) have identified specific genetic variants associated with various fever outcomes. For example, variation at the HLA-DRB1 gene is linked to resistance against enteric fever. [1] Similarly, susceptibility to dengue shock syndrome has been associated with loci at MICB and PLCE1 [6] while fatal outcomes from Lassa fever are also tied to specific human genetic variants. [2]
In allergic conditions like hay fever, a shared genetic origin with asthma and eczema has been elucidated, highlighting common genetic architectures underlying these hypersensitivity diseases . [4], [7], [8] The HLA-DQB1 gene, specifically the Gly45 amino acid polymorphism within its peptide-binding cleft, has been associated with scarlet fever. [3] These genetic associations, often involving genes critical for immune responses and host defense, underscore the role of inherited factors in modulating disease susceptibility and severity across a spectrum of fever-related conditions.
Pathophysiological Processes and Biomolecules
Fever conditions arise from diverse pathophysiological processes that disrupt homeostasis and involve critical biomolecules. Enteric fever, for example, is characterized by the interaction between the human host and the Salmonella Typhi pathogen, where host genetic determinants influence susceptibility. [1] In dengue, differing influences of virus burden and immune activation correlate with disease severity, indicating a complex interplay of host response and viral factors. [6] The long-term effects of tumour necrosis factor (TNF) excess on the immune system also highlight a key biomolecule involved in inflammatory responses that can contribute to fever. [9]
Allergic fevers, such as hay fever, involve a distinct set of pathophysiological processes where the FLG gene is crucial for the formation and hydration of the stratum corneum, the outermost layer of the skin. [7] Mutations in FLG can lead to a compromised skin barrier, making individuals sensitive to external allergens and triggering a strong allergic immune response that manifests systemically. [7] This demonstrates how a genetic defect in a structural component can lead to widespread immune dysregulation, reflecting the intricate connection between genetic mechanisms, key biomolecules, and the overall pathophysiological landscape of fever.
Systemic and Tissue-Level Manifestations
Fever conditions often present with systemic consequences and tissue-specific effects, reflecting widespread biological disruptions. In allergic diseases like hay fever, the underlying genetics and molecular pathways show overlap with skin tissue diseases, such as eczema, and respiratory conditions like asthma. [7] This connection is exemplified by the FLG gene, where mutations can cause dry, flaky skin and simultaneously activate a strong allergic immune response in the peripheral blood that leads to inflammation in organs like the lungs, resulting in symptoms such as shortness of breath. [7] This indicates a systemic allergic predisposition impacting multiple organ systems.
Beyond allergic fevers, infectious fevers also demonstrate significant systemic and tissue-level impacts. For instance, early whole-blood transcriptional signatures are observed in dengue virus infections, providing insights into the systemic immune response and features associated with the progression to dengue shock syndrome. [6] In scarlet fever, T cells generated by palatine tonsils can recognize skin keratin determinants, suggesting a tissue-specific immune interaction that contributes to the disease's manifestations. [3] These examples highlight how diverse fever etiologies lead to interconnected responses across tissues and organs, from localized immune activity to broad systemic inflammation.
Initiation of Inflammatory Signaling
Fever often originates from immune responses triggered by the recognition of pathogens. Toll-like receptors (TLR3 and TLR4) play a critical role in sensing microbial components, and their downstream signaling pathways involve adaptor molecules such as TRIF. The metalloproteinase ADAM15 is known to cleave TRIF, suggesting a mechanism for modulating the innate immune response. [5] Concurrently, the ligase TRIM8 negatively regulates TLR3/4-mediated innate immune responses by blocking the interaction between TRIF and TBK1, thereby impacting the intensity and duration of inflammatory signaling cascades. [5]
Intracellular signaling networks activated by pro-inflammatory cytokines are central to fever pathogenesis. TNFalpha and IL-1beta are potent cytokines that trigger NF-kappaB activation, a key transcription factor that regulates the expression of numerous genes involved in inflammation. [5] TRIM8 further modulates TNFalpha- and IL-1beta-triggered NF-kappaB activation by targeting TAK1 for K63-linked polyubiquitination, which is essential for signal transduction. [5] Additionally, the protein-tyrosine kinase PYK2 is phosphorylated in human neutrophils stimulated by TNFalpha and fMLP when adherent to fibrinogen, contributing to immune cell activation and inflammatory responses. [4] The NKG2D receptor, which assembles into a hexameric structure with signaling dimers, also participates in the initiation of immune activation. [6]
Genetic and Post-Translational Regulation of Immune Responses
Genetic variations significantly influence an individual's susceptibility and the severity of fever-inducing infections. For instance, variation at HLA-DRB1 is associated with resistance to enteric fever, highlighting the critical role of Major Histocompatibility Complex (MHC) molecules in presenting antigens and shaping host defense. [1] HLA alleles are known to impact gene expression in primary immune cells and are central to antigen processing pathways, which dictate how the immune system recognizes and mounts a response against pathogens. [3] These genetic determinants contribute to the complex immune landscape and can influence the outcome of infectious diseases.
Beyond direct genetic predispositions, gene regulation and post-translational modifications finely tune immune cell function. FOSL2 (Fra-2/AP-1) regulates B cell development and Th17 cell and epidermal differentiation by enhancing IRF4 and Foxo1 transcription, thereby influencing adaptive immune responses. [5] Similarly, miR-155 promotes the accumulation of T follicular helper cells, which are crucial for effective antibody production and sustained immune memory. [4] Post-translational modifications, such as the ubiquitination of TAK1 and TRIF by the ligase TRIM8, play a significant role in modulating NF-kappaB activation and innate immune signaling. [5] Furthermore, SRC1 promotes Th17 differentiation by stimulating ROR-gammat activity in a PKC-theta-dependent manner, illustrating the intricate regulatory networks governing immune cell fate and inflammatory responses. [5]
Metabolic Modulation and Cellular Differentiation
Metabolic pathways within immune cells are intrinsically linked to their function and the overall immune response that can contribute to fever. For instance, murine plasmacytoid dendritic cells initiate the immunosuppressive pathway of tryptophan catabolism in response to CD200 receptor engagement. [5] This metabolic reprogramming can influence the local immune environment, potentially regulating the intensity or duration of inflammation and fever. The intricate interplay between the metabolic state of immune cells and their activation status is a critical determinant of host defense and inflammatory outcomes.
Cellular differentiation and broader signaling pathways, beyond immediate pathogen recognition, also contribute to the systemic response observed in fever. BMPR2, a receptor for the TGF-beta superfamily, is involved in inhibiting Smad-mediated signaling. [5] This pathway is crucial for various cellular processes including inflammation, cell proliferation, and tissue repair, and its precise regulation can influence the broader physiological responses associated with fever. The intricate cross-talk between these diverse signaling mechanisms and metabolic processes contributes to the complex and integrated manifestation of fever.
Systems-Level Disease Pathogenesis and Therapeutic Targets
The manifestation of fever often represents a systems-level integration of multiple interacting pathways, where dysregulation can lead to severe disease outcomes. Genetic variants are associated with fatal outcomes from Lassa fever, indicating critical host determinants in severe infectious disease. [2] Similarly, susceptibility loci for dengue shock syndrome have been identified at MICB and PLCE1, emphasizing the genetic architecture underlying the host response to viral infections. [6] The complex host-pathogen interface plays a critical role in determining the outcome of infections like enteric fever, where pathogen virulence mechanisms interact with host immune responses to shape disease progression. [1]
Understanding these complex interactions reveals potential disease-relevant mechanisms and therapeutic targets. For instance, rare genetic diseases involving mutations in the IL-12 or IFN-γ pathways result in hypersusceptibility to non-typhoidal Salmonella and other intracellular bacteria, demonstrating how specific pathway dysfunctions can severely impair host defense. [1] In the context of allergic diseases, which can manifest with fever, ADAM15 is known to cleave the low affinity IgE receptor, a mechanism relevant to allergic inflammation. [5] These insights into pathway dysregulation and compensatory mechanisms offer crucial avenues for developing targeted interventions to mitigate severe fever-related pathologies.
Genetic Modulators of Inflammatory Pathways and Fever Severity
Fever is a cardinal sign of systemic inflammation, and an individual's genetic makeup significantly influences the intensity and duration of this response. Variants in genes encoding key inflammatory mediators, such as TNF, LTA, IL1B, IL6, IL8, and CCL, have been investigated for their association with the severity and outcome of infectious diseases like pandemic influenza A/H1N1. [10] These genetic polymorphisms can alter the expression or function of these cytokines, thereby modulating the febrile response and the overall inflammatory cascade. Furthermore, genome-wide association studies have identified numerous loci that influence the circulating concentrations of various cytokines and growth factors, demonstrating a broad genetic control over these immune components. [11] Such genetic predispositions contribute to inter-individual variability in fever presentation and the underlying inflammatory state, potentially impacting the effectiveness of therapeutic interventions aimed at mitigating these symptoms.
Host Genetic Factors Influencing Immune Response and Therapeutic Outcomes
Beyond direct inflammatory mediators, host genetic variations in components of the immune system can profoundly affect the body's response to pathogens and, consequently, the severity of associated fever and the efficacy of supportive treatments. For instance, specific genetic variants in IFITM3 have been shown to restrict the morbidity and mortality associated with influenza, while functional variations in CD55 can influence influenza severity. [10] These host genetic factors, including HLA class II sequence variants, which are known to influence susceptibility to infections like tuberculosis, play a critical role in shaping the immune response that drives fever. [12] Understanding these genetic determinants of immune competence is vital, as they can dictate the overall therapeutic response and the need for personalized approaches to manage febrile illnesses and prevent adverse reactions. The genetic architecture of the human immune system, including variants regulating immune cell levels, is a significant determinant of disease pathogenesis and therapeutic outcomes. [13]
Genetic Predisposition to Adverse Drug Reactions and Personalized Management
Genetic variability also underlies an individual's susceptibility to adverse drug reactions (ADRs), a crucial consideration in the pharmacological management of any condition, including those accompanied by fever. A notable example is the strong association between specific HLA genotypes and antithyroid drug-induced agranulocytosis, illustrating how immune system genetics can predispose individuals to severe, idiosyncratic drug reactions. [14] While this example pertains to a specific drug class, the principle of genetically determined ADR risk is broadly applicable across pharmacotherapy. Integrating such pharmacogenetic insights into clinical practice allows for more personalized prescribing, potentially informing drug selection or dosing adjustments to mitigate risks and enhance safety, especially for patients with complex febrile conditions where multiple medications may be administered. This approach aims to optimize therapeutic benefit while minimizing harm based on an individual's unique genetic profile.
Key Variants
| RS ID | Gene | Related Traits |
|---|---|---|
| rs144384547 | RNA5SP224 - RNA5SP225 | fever |
| rs77344822 | OTUD7A | fever |
| rs79301185 | ADRA1A - MIR548H4 | fever |
| rs192688594 | LINC00358 - LINC01075 | fever |
| rs200973787 | CDC14A | fever |
| rs397822879 | TPTEP2-CSNK1E - KCNJ4 | fever |
| rs17181171 | OPRM1 | fever |
| rs28360654 | PDE10A | fever |
| rs4784797 | RPL23AP91 - CCL22 | fever |
Frequently Asked Questions About Fever
These questions address the most important and specific aspects of fever based on current genetic research.
1. Why do I get sicker with fevers than my friends?
Your genes can play a significant role in how severely you react to infections that cause fever. For instance, specific human genetic variants have been linked to the fatal outcome of Lassa fever. Your unique genetic makeup influences how effectively your immune system responds to pathogens, affecting the intensity and duration of your fever symptoms compared to others.
2. Does my family history mean I'll get more fevers?
Yes, there can be a genetic component to how your family experiences fevers. Conditions like hay fever, which can sometimes be confused with infectious fevers, share a genetic origin with other allergic diseases. Additionally, the HLA region, which is highly variable and inherited, contains susceptibility loci for many common infections, suggesting a familial pattern for certain fever-inducing conditions.
3. Am I more likely to catch certain fevers because of my genes?
Yes, your genetic makeup can influence your susceptibility to specific infections that cause fever. For example, variations in the HLA-DRB1 gene are associated with resistance to enteric fever. Also, a specific amino acid polymorphism HLA-DQB1 Gly45 (rs36205178) in the HLA-DQB1 gene is linked to scarlet fever, affecting how your immune system recognizes pathogens.
4. Why do I get hay fever but my sibling doesn't?
Even within families, genetic predispositions can manifest differently. While hay fever shares a genetic origin with conditions like asthma and eczema, the exact combination of genetic variants you inherited, along with your unique environmental exposures, might differ from your sibling. This can lead to one sibling developing allergic conditions like hay fever while the other does not.
5. Does my family's ancestry affect my risk for certain fevers?
Yes, your family's ancestry can influence your genetic risk for certain fever-inducing conditions. Genetic findings are often specific to the populations studied due to variations in gene frequencies and linkage disequilibrium structures across different ethnic groups. Research predominantly on individuals of European descent might not fully capture unique genetic risks or protective factors present in other ancestral populations.
6. If fever helps me fight illness, why do I feel so awful?
It's true that fever is an adaptive response designed to help your body fight infection by inhibiting pathogen growth and enhancing immune function. However, the processes your body undertakes to raise and maintain that higher temperature, like increasing heat production (e.g., shivering) and decreasing heat loss (e.g., vasoconstriction), along with the general immune response, are energy-intensive and can make you feel unwell.
7. Could a DNA test predict if I'll get bad fevers?
A DNA test could potentially offer some insights into your genetic predispositions for certain fever-related conditions. Genetic studies have identified specific variants, such as rs7765379 in the HLA region, linked to susceptibility or outcomes for conditions like enteric fever or scarlet fever. However, these tests usually provide risk probabilities, and fever severity is complex, influenced by many genes and environmental factors.
8. Why do some people never get a fever with a cold, but I always do?
Your genetic makeup plays a significant role in how your immune system responds to common infections like colds. Some individuals may have genetic variations that lead to a more robust or different initial immune response, resulting in a noticeable fever, while others might manage the infection without reaching the fever threshold. These host determinants influence your body's specific reaction to pyrogens.
9. Can I overcome my genes if I'm prone to bad fevers?
While your genes certainly influence your susceptibility and response to fever-inducing conditions, environmental factors also play a substantial role. Maintaining a healthy lifestyle, including good nutrition, adequate sleep, and managing stress, can support your immune system. This can help your body respond more effectively to infections, potentially mitigating the impact of certain genetic predispositions.
10. Does stress make me get fevers more easily?
Yes, chronic stress can influence your immune system, potentially making you more susceptible to infections and thus to developing fevers. While genetic factors determine your baseline immune response, environmental factors like stress can interact with your genes. This interplay can affect your body's ability to fight off pathogens, potentially leading to more frequent or more pronounced fever responses when you are exposed to illness.
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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[2] Kotliar D, et al. Genome-wide association study identifies human genetic variants associated with fatal outcome from Lassa fever. Nat Microbiol. 2024 Mar;9(3):611-625.
[3] Tian C, et al. Genome-wide association and HLA region fine-mapping studies identify susceptibility loci for multiple common infections. Nat Commun. 2017 Sep 19;8(1):599.
[4] Ferreira, M. A., et al. "Shared genetic origin of asthma, hay fever and eczema elucidates allergic disease biology." Nat Genet, vol. 49, 2017, pp. 1752–7. PMID: 29083406.
[5] Ferreira MAR, et al. Age-of-onset information helps identify 76 genetic variants associated with allergic disease. PLoS Genet. 2020 Jun 29;16(6):e1008821.
[6] Khor CC, et al. Genome-wide association study identifies susceptibility loci for dengue shock syndrome at MICB and PLCE1. Nat Genet. 2011 Nov 13;43(12):1185-91.
[7] Zhu, Z., et al. (2018). A genome-wide cross-trait analysis from UK Biobank highlights the shared genetic architecture of asthma and allergic diseases. Nat. Genet., 50, 857–864.
[8] Johansson, A., A. Ganna, A. Sanniti, et al. "Genome-wide association analysis of 350 000 Caucasians from the UK Biobank identifies novel loci for asthma, hay fever and eczema." Hum Mol Genet, 2019.
[9] Clark, J., Vagenas, P., Panesar, M., & Cope, A. P. (2005). What does tumour necrosis factor excess do to the immune system long term. Ann. Rheum Dis., 64, iv70–iv76.
[10] Garcia-Etxebarria, K., et al. "No Major Host Genetic Risk Factor Contributed to A(H1N1)2009 Influenza Severity." PLoS One, vol. 10, no. 9, 2015, e0137211.
[11] Ahola-Olli, A. V., et al. "Genome-wide association study identifies 27 loci influencing concentrations of circulating cytokines and growth factors." American Journal of Human Genetics, vol. 100, no. 1, 2017, pp. 40–50.
[12] Butler-Laporte, G., et al. "Genetic Determinants of Antibody-Mediated Immune Responses to Infectious Diseases Agents: A Genome-Wide and HLA Association Study." Open Forum Infectious Diseases, vol. 7, no. 11, 2020, ofaa529.
[13] Roederer, M., et al. "The genetic architecture of the human immune system: a bioresource for autoimmunity and disease pathogenesis." Cell, vol. 161, 2015, pp. 387–403.
[14] Chen, P. L., et al. "Genetic determinants of antithyroid drug-induced agranulocytosis by human leukocyte antigen genotyping and genome-wide association study." Nature Communications, vol. 6, 2015, 7632.