Tag: SNPs

Actigraphic and Genetic Characterization of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Phenotypes in the UK Biobank (P10-9.007)

Abstract:

Objective: Patients with myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) often experience debilitating fatigue and autonomic dysregulation, yet objective measurements of these symptoms are limited. This study utilized actigraphic data from the United Kingdom Biobank (UKBB) to investigate (1) reduced activity in those with CFS, (2) decreased amplitudes of daily temperature rhythms as a potential indicator of autonomic dysregulation, and (3) the impact of specific single nucleotide polymorphisms (SNPs) associated with CFS on these actigraphic parameters.

Background: ME/CFS is a complex and poorly understood condition characterized by profound fatigue, postural orthostasis, and temperature dysregulation. Objective metrics reflecting these fatigue-related symptoms are scarce. Previous research explored small-scale actigraphic analyses, shedding light on movement and temperature patterns in CFS, but large-scale investigations remain limited. Genetic factors have also emerged as potential contributors to CFS risk, although how they affect phenotypic manifestations remains unclear.

Design/Methods: Actigraphic data from the UKBB were analyzed to compare those with CFS (n = 295) to controls (n = 63,133). Movement parameters, acceleration amplitudes, and temperature amplitudes were assessed. Additionally, the impact of specific SNPs associated with CFS on actigraphic measurements and subjective fatigue experiences was examined.

Results: In addition to profound fatigue, those with CFS exhibited significantly reduced overall movement (Cohen’s d = −0.220, p-value = 2.42 × 10–15), lower acceleration amplitudes (Cohen’s d = −0.377, p-value = 1.74 × 10−6), and decreased temperature amplitudes (Cohen’s d = −0.173, p-value = 0.002) compared to controls. Furthermore, certain SNPs associated with CFS were found to significantly influence both actigraphic measurements and subjective fatigue experiences.

Conclusions: This study provides valuable insights into the objective characterization of CFS using actigraphy, shedding light on the interaction between genetics and symptomatology in CFS. The findings offer avenues for further research into the pathophysiology of CFS and may contribute to a better understanding of fatigue-related conditions in general.

Source: Patrick Liu, David Raizen, Carsten Skarke, Thomas Brooks, and Ron Anafi. Actigraphic and Genetic Characterization of Myalgic Encephalomyelitis/Chronic Fatigue Syndrome Phenotypes in the UK Biobank (P10-9.007). Neurology, April 9, 2024 issue
102 (17_supplement_1) https://doi.org/10.1212/WNL.0000000000204829 https://www.neurology.org/doi/abs/10.1212/WNL.0000000000204829

Host genetic polymorphisms involved in long-term symptoms of COVID-19

Abstract:

Host genetic polymorphisms are recognized as a critical determinant of diversity in clinical symptoms of Coronavirus disease 2019 (COVID-19). Accordingly, this study aimed to determine possible associations between single nucleotide polymorphisms (SNPs) in 37 candidate genetic variants and clinical consequences of COVID-19 – especially long-term symptoms, Long COVID.

A total of 260 COVID-19 patients, divided into mild (n = 239) and severe (n = 21) and further categorized based on the presence of Long COVID (no, n = 211; yes, n = 49), were recruited. Genotyping of selected polymorphisms responsible for viral entry, immune response, and inflammation was performed using MassARRAY system.

Out of 37 SNPs, 9 including leucine zipper transcription factor like-1 (LZTFL1) rs10490770 C allele, LZTFL1 rs11385942 dupA allele, nicotinamide adenine dinucleotide synthetase-1 (NADSYN1) rs12785878 TT genotype, plexin A-4 (PLXNA4) rs1424597 AA genotype, LZTFL1 rs17713054 A allele, interleukin-10 (IL10) rs1800896 TC genotype and C allele, angiotensin converting enzyme-2 (ACE2) rs2285666 T allele, and plasmanylethanolamine desaturase-1 (PEDS1) rs6020298 GG genotype and G allele were significantly associated with an increased risk of developing Long COVID, whereas interleukin-10 receptor subunit beta (IL10RB) rs8178562 GG genotype was significantly associated with a reduced risk of Long COVID. Kaplan-Meier curve displayed that the above gene polymorphisms were significantly associated with cumulative rate of Long COVID occurrence.

Polymorphisms in LZTFL1 rs10490770,  LZTFL1 rs11385942,  LZTFL1 rs17713054,  NADSYN1 rs12785878,  PLXNA4 rs1424597, IL10 rs1800896,  ACE2 rs2285666, PEDS1 rs6020298, and IL10RB rs8178562 appear to be genetic factors involved in development of Long COVID.

Source: Udomsinprasert W, Nontawong N, Saengsiwaritt W, Panthan B, Jiaranai P, Thongchompoo N, Santon S, Runcharoen C, Sensorn I, Jittikoon J, Chaikledkaew U, Chantratita W. Host genetic polymorphisms involved in long-term symptoms of COVID-19. Emerg Microbes Infect. 2023 Dec;12(2):2239952. doi: 10.1080/22221751.2023.2239952. PMID: 37497655; PMCID: PMC10392286. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC10392286/ (Full text)

Genetic risk factors for ME/CFS identified using combinatorial analysis

Abstract:

Background:Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a debilitating chronic disease that lacks known pathogenesis, distinctive diagnostic criteria, and effective treatment options. Understanding the genetic (and other) risk factors associated with the disease would begin to help to alleviate some of these issues for patients.

Methods: We applied both GWAS and the PrecisionLife combinatorial analytics platform to analyze ME/CFS cohorts from UK Biobank, including the Pain Questionnaire cohort, in a case-control design with 1,000 cycles of fully random permutation. Results from this study were supported by a series of replication and cohort comparison experiments, including use of disjoint Verbal Interview CFS, post-viral fatigue syndrome and fibromyalgia cohorts also derived from UK Biobank, and results compared for overlap and reproducibility.

Results: Combinatorial analysis revealed 199 SNPs mapping to 14 genes, that were significantly associated with 91% of the cases in the ME/CFS population. These SNPs were found to stratify by shared cases into 15 clusters (communities) made up of 84 high-order combinations of between 3-5 SNPs. p-values for these communities range from 2.3 × 10−10 to 1.6 × 10−72. Many of the genes identified are linked to the key cellular mechanisms hypothesized to underpin ME/CFS, including vulnerabilities to stress and/or infection, mitochondrial dysfunction, sleep disturbance and autoimmune development. We identified 3 of the critical SNPs replicated in the post-viral fatigue syndrome cohort and 2 SNPs replicated in the fibromyalgia cohort. We also noted similarities with genes associated with multiple sclerosis and long COVID, which share some symptoms and potentially a viral infection trigger with ME/CFS.

Conclusions: This study provides the first detailed genetic insights into the pathophysiological mechanisms underpinning ME/CFS and offers new approaches for better diagnosis and treatment of patients

Source: Sayoni Das, Krystyna Taylor, James Kozubek, Jason Sardell, Steve Gardner. Genetic Risk Factors for ME/CFS Identified using Combinatorial Analysis. medRxiv 2022.09.09.22279773; doi: https://doi.org/10.1101/2022.09.09.22279773  https://www.medrxiv.org/content/10.1101/2022.09.09.22279773v2.full-text (Full text)

No replication of previously reported association with genetic variants in the T cell receptor alpha (TRA) locus for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)

Abstract:

Myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) is a disease with a variety of symptoms such as post-exertional malaise, fatigue, and pain, but where aetiology and pathogenesis are unknown. An increasing number of studies have implicated the involvement of the immune system in ME/CFS. Furthermore, a hereditary component is suggested by the reported increased risk for disease in relatives, and genetic association studies are being performed to identify potential risk variants.

We recently reported an association with the immunologically important human leucocyte antigen (HLA) genes HLA-C and HLA-DQB1 in ME/CFS. Furthermore, a genome-wide genetic association study in 42 ME/CFS patients reported significant association signals with two variants in the T cell receptor alpha (TRA) locus (P value <5 × 10-8). As the T cell receptors interact with the HLA molecules, we aimed to replicate the previously reported findings in the TRA locus using a large Norwegian ME/CFS cohort (409 cases and 810 controls) and data from the UK biobank (2105 cases and 4786 controls).

We investigated numerous SNPs in the TRA locus, including the two previously ME/CFS-associated variants, rs11157573 and rs17255510. No associations were observed in the Norwegian cohort, and there was no significant association with the two previously reported SNPs in any of the cohorts. However, other SNPs showed signs of association (P value <0.05) in the UK Biobank cohort and meta-analyses of Norwegian and UK biobank cohorts, but none survived correction for multiple testing. Hence, our research did not identify any reliable associations with variants in the TRA locus.

Source: Ueland M, Hajdarevic R, Mella O, Strand EB, Sosa DD, Saugstad OD, Fluge Ø, Lie BA, Viken MK. No replication of previously reported association with genetic variants in the T cell receptor alpha (TRA) locus for myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS). Transl Psychiatry. 2022 Jul 11;12(1):277. doi: 10.1038/s41398-022-02046-1. PMID: 35821115. https://www.nature.com/articles/s41398-022-02046-1 (Full text)

Immunogenetic studies in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS)

Myalgic encephalopathy/chronic fatigue syndrome (ME/CFS) is a chronic and debilitating disease that affects about 0.1-0.2% of the general population. The core symptoms are persistent debilitating fatigue, post-exertional malaise (PEM) and cognitive dysfunction. Most symptoms of ME/CFS are not disease specific. Additionally, there is a lack of both biomarkers and diagnostic tests for the disease, which makes accurate diagnosis difficult.

More than 20 different patient classifications and diagnostic criteria have emerged over the last four decades. Due to this, the patient population can be quite heterogeneous in terms of clinical symptoms and the extent to which the disease impacts quality of life.

There are several different theories that aim to explain the disease development of ME/CFS. In this thesis, we have taken as our starting point the growing evidence for an immunological background for ME/CFS pathogenesis. Several studies have pointed to altered NK cells, autoantibodies and T cell abnormalities in ME/CFS patients.

In addition, several genetic studies reported significant associations in various immunologically relevant genes. Most of these previous studies have been suboptimal and included heterogeneous patient populations and/or few patients in total.

Therefore, we aimed to gain a better understanding of the role of immunologically relevant genes and disease development of ME/CFS.

To do this, we employed known strategies from genetic studies in autoimmune disease and applied them to ME/CFS. We used strict quality control and included, to the best of our knowledge, the largest cohort diagnosed with the Canadian consensus criteria.

In paper I, the main goal was to follow up previously performed work by our group that reported associations between ME/CFS and HLA-C: 07: 04 and HLA-DQB1: 03: 03 alleles. The HLA (human leukocyte antigen) region consists a multitude of immunologically relevant genes in addition to the HLA genes, and there is extensive and complex linkage disequilibrium (LD) in the region.

The previously observed association signals in the HLA region were fine-mapped by genotyping five additional classical HLA loci and 5,342 SNPs (single nucleotide variants) in 427 Norwegian ME/CFS patients, diagnosed according to the Canadian consensus criteria, and 480 healthy Norwegian controls. The analysis revealed two independent association signals (p ≤ 0.001) represented by the genetic variants rs4711249 in the HLA class I region and rs9275582 in the HLA class II region.

The primary association signal in the HLA class II region was located in the vicinity of the HLA-DQ genetic region, most likely due to the HLA-DQB1 gene. In particular, amino acid position 57 (aspartic acid / alanine) in the peptide binding pit of HLA-DQB1, or an SNP upstream of HLA-DQB1 seemed to explain the association signal we observed in the HLA class II region.

In the HLA class I region, the putative primary locus was not as clear and could possibly lie outside the classical HLA genes (the association signal spans several genes DDR1, GTF2H4, VARS2, SFTA2 and DPCR1) with expression levels influenced by the ME/CFS associated SNP genotypes.

Interestingly, we also observed that > 60% of the patients who responded to cyclophosphamide treatment for ME/CFS had either the rs4711249 risk allele and/or DQB1* 03:03 versus 12% of the patients who did not respond to the treatment. Our findings suggest the involvement of the HLA region, and in particular the HLA-DQB1 gene, in ME/CFS.

Although our study is the largest to date, it is still a relatively small study in the context of genetic studies. Our findings need to be replicated in much larger, statistically more representative, cohorts.

In particular, it is necessary to investigate the involvement of HLA- 12 DQB1, a gene that contains alleles that increase the risk of several established autoimmune diseases such as celiac disease.

In paper II, we aimed to investigate immunologically relevant genes using a genotyping array (iChip) targeting immunological gene regions previously associated with different autoimmune diseases.

In addition to the Norwegian cohort of 427 ME/CFS patients (the Canadian consensus criteria), we also analyzed data from two replication cohorts, a Danish one of 460 ME/CFS patients (Canadian consensus criteria) and a data set from the UK Biobank of 2105 self-reported CFS patients.

To the best of our knowledge, this is the first ME/CFS genetic association study of this magnitude and it included more than 2,900 patients in total (of whom 887 are diagnosed according to Canadian consensus criteria).

We found no ME/CFS risk variants with a genome wide significance level (p<5×10-8), but we identified six gene regions (TPPP, LINC00333, RIN3. IGFBP/IGFBP3, IZUMO1/MAMSTR and ZBTB46/STMN3) with possible association with ME/CFS which require further follow-up in future studies in order to assess whether they are real findings or not.

Interestingly, these genes are expressed in disease-relevant tissue, e.g. brain, nerve, skeletal muscle and blood, including immune cells (subgroups of T cells, B cells, NK cells and monocytes).

Furthermore, several of the ME/CFS associated SNP genotypes are associated with differential expression levels of these genes. Although we could not identify statistically convincing associations with genetic variants across the three cohorts, we believe that our data sets and analysis represent an important step in the ME/CFS research field.

Our study demonstrated that for the future understanding of the genetic architecture of ME/CFS much larger studies are required to established reliable associations.

In paper III, we wanted to investigate previous findings from a genome wide association study of 42 ME/CFS patients who reported significant association with two SNPs in the T cell receptor alpha (TRA) locus (P-value<5×10-8).

In order to replicate these previously reported findings, we used a large Norwegian ME/CFS cohort (409 cases and 810 controls) and data from the UK Biobank (2105 cases and 4786 controls). We examined a number of SNPs in the TRA locus, including the two previous ME/CFS-associated variants, rs11157573 and rs17255510. No statistically significant associations were observed in either the Norwegian cohort or UK biobank cohorts.

Nevertheless, other SNPs in the region showed weak signs of association (P-value <0.05) in the UK Biobank cohort and meta-analyzes of Norwegian and UK Biobank cohorts, but did not remain associated after applying correction for multiple testing. Thus, we could not confirm associations with genetic variants in the TRA locus in this study.

Source: Riad Hajdarevic. PhD thesis (University of Oslo) Electronic copies must be ordered. https://www.med.uio.no/klinmed/english/research/news-and-events/events/disputations/2022/hajdarevic-riad.html

Fine mapping of the major histocompatibility complex (MHC) in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) suggests involvement of both HLA class I and class II loci

Abstract:

The etiology of myalgic Encephalomyelitis/Chronic Fatigue Syndrome (ME/CFS) is unknown, but involvement of the immune system is one of the proposed underlying mechanisms. Human leukocyte antigen (HLA) associations are hallmarks of immune-mediated and autoimmune diseases. We have previously performed high resolution HLA genotyping and detected associations between ME/CFS and certain HLA class I and class II alleles. However, the HLA complex harbors numerous genes of immunological importance, and there is extensive and complex linkage disequilibrium across the region. In the current study, we aimed to fine map the association signals in the HLA complex by genotyping five additional classical HLA loci and 5,342 SNPs in 427 Norwegian ME/CFS patients, diagnosed according to the Canadian Consensus Criteria, and 480 healthy Norwegian controls.

SNP association analysis revealed two distinct and independent association signals (p≤0.001) tagged by rs4711249 in the HLA class I region and rs9275582 in the HLA class II region. Furthermore, the primary association signal in the HLA class II region was located within the HLA-DQ gene region, most likely due to HLA-DQB1, particularly the amino acid position 57 (aspartic acid/alanine) in the peptide binding groove, or an intergenic SNP upstream of HLA-DQB1. In the HLA class I region, the putative causal locus might map outside the classical HLA genes as the association signal spans several genes (DDR1, GTF2H4, VARS2, SFTA2 and DPCR1) with expression levels influenced by the ME/CFS associated SNP genotype.

Taken together, our results implicate the involvement of the MHC, and in particular the HLA-DQB1 gene, in ME/CFS. These findings should be replicated in larger cohorts, particularly to verify the putative involvement of HLA-DQB1, a gene important for antigen-presentation to T cells and known to harbor alleles providing the largest risk for well-established autoimmune diseases.

Source: Hajdarevic R, Lande A, Rekeland I, Rydland A, Strand EB, Sosa DD, Creary LE, Mella O, Egeland T, Saugstad OD, Fluge Ø, Lie BA, Viken MK. Fine mapping of the major histocompatibility complex (MHC) in myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) suggests involvement of both HLA class I and class II loci. Brain Behav Immun. 2021 Aug 14:S0889-1591(21)00509-2. doi: 10.1016/j.bbi.2021.08.219. Epub ahead of print. PMID: 34403736. https://pubmed.ncbi.nlm.nih.gov/34403736/

Re-analysis of genetic risks for Chronic Fatigue Syndrome from 23andMe data finds few remain

Abstract:

It is tempting to mine the abundance of DNA data that is now available from direct-to-consumer genetic tests but this approach also has its pitfalls A recent study put forth a list of 50 single nucleotide polymorphisms (SNPs) that predispose to Chronic Fatigue Syndrome (CFS), a potentially major advance in understanding this still mysterious condition. However, only the patient cohort data came from a commercial company (23andMe) while the control was from a genetic database. The extent to which 23andMe data agree with genetic reference databases is unknown.

We reanalyzed the 50 purported CFS SNPs by comparing to control data specifically from 23andMe which are available through public platform OpenSNP. In addition, large high-quality database ALFA was used as an additional control. The analysis lead to dramatic change with the top of the leaderboard for CFS risk reduced and reversed from an astronomical 129,000 times to 0.8. Errors were found both within 23andMe data and the original study-reported Kaviar database control. Only 3 of 50 SNPs survived initial study criterion of at least twice as prevalent in patients, EFCAB4B, involved in calcium ion channel activation, LINC01171, and MORN2 genes.

We conclude that the reported top-50 deleterious polymorphisms for Chronic Fatigue Syndrome were more likely the top-50 errors in the 23andMe and Kaviar databases. In general, however, correlation of 23andMe control with ALFA was a respectable 0.93, suggesting an overall usefulness of 23andMe results for research purposes but only if caution is taken with chips and SNPs.

Source: Felice L. Bedford, Bastian Greshake Tzovaras. Re-analysis of genetic risks for Chronic Fatigue Syndrome from 23andMe data finds few remain. medRxiv 2020.10.27.20220939; doi: https://doi.org/10.1101/2020.10.27.20220939
Now published in Frontiers in Pediatrics doi: 10.3389/fped.2021.590040 https://www.medrxiv.org/content/10.1101/2020.10.27.20220939v2.full-text (Full text)

Re-analysis of genetic risks for Chronic Fatigue Syndrome from 23andMe data finds few remain

Abstract:

It is tempting to mine the abundance of DNA data that is now available from direct-to-consumer genetic tests, but this approach has its pitfalls A recent study put forth a list of 50 single nucleotide polymorphisms (SNPs) that predispose to Chronic Fatigue Syndrome (CFS), a potentially major advance in understanding this still mysterious disease. However, only the patient cohort data came from a commercial company (23andMe) while the control was a genetic database. The extent to which 23andMe data agree with genetic reference databases is unknown. We reanalyzed the 50 purported CFS SNPs by comparing to control data from 23andMe which are available through public platform OpenSNP. In addition, large high-quality database ALFA was used as an additional control. The analysis lead to dramatic change with the top of the leaderboard for CFS risk reduced and reversed from an astronomical 129,000 times to 0.8.

Errors were found both within 23andMe data and the original study-reported Kaviar database control. Only 3 of 50 SNPs survived initial study criterion of at least twice as prevalent in patients, EFCAB4B involving calcium ion channel, LINC01171, and MORN2 genes. We conclude the reported top-50 deleterious polymorphisms for Chronic Fatigue Syndrome were more likely the top-50 errors in the 23andMe and Kaviar databases. In general, however, correlation of 23andMe control with ALFA was a respectable 0.93, suggesting an overall usefulness of 23andMe results for research purposes but only if caution is taken with chips and SNPs.

Source: Felice L Bedford, Bastian Greshake Tzovaras. Re-analysis of genetic risks for Chronic Fatigue Syndrome from 23andMe data finds few remain. Frontiers in Pediatrics, October 29. 2020. https://www.medrxiv.org/content/10.1101/2020.10.27.20220939v1.full.pdf+html  (Full study)

Autoimmunity-Related Risk Variants in PTPN22 and CTLA4 Are Associated With ME/CFS With Infectious Onset

Abstract:

Single nucleotide polymorphisms (SNP) in various genes have been described to be associated with susceptibility to autoimmune disease. In this study, myalgic encephalomyelitis/chronic fatigue syndrome (ME/CFS) patients and controls were genotyped for five immune gene SNPs in tyrosine phosphatase non-receptor type 22 (PTPN22, rs2476601), cytotoxic T-lymphocyte-associated protein 4 (CTLA4, rs3087243), tumor necrosis factor (TNF, rs1800629 and rs1799724), and interferon regulatory factor 5 (IRF5, rs3807306), which are among the most important risk variants for autoimmune diseases.

Analysis of 305 ME/CFS patients and 201 healthy controls showed significant associations of the PTPN22 rs2476601 and CTLA4 rs3087243 autoimmunity-risk alleles with ME/CFS. The associations were only found in ME/CFS patients, who reported an acute onset of disease with an infection (PTPN22 rs2476601: OR 1.63, CI 1.04-2.55, p = 0.016; CTLA4 rs3087243: OR 1.53, CI 1.17-2.03, p = 0.001), but not in ME/CFS patients without infection-triggered onset (PTPN22 rs2476601: OR 1.09, CI 0.56-2.14, p = 0.398; CTLA4 rs3087243: OR 0.89, CI 0.61-1.30, p = 0.268). This finding provides evidence that autoimmunity might play a role in ME/CFS with an infection-triggered onset. Both genes play a key role in regulating B and T cell activation.

Source: Steiner S, Becker SC, Hartwig J, Sotzny F, Lorenz S, Bauer S, Löbel M, Stittrich AB, Grabowski P, Scheibenbogen C. Autoimmunity-Related Risk Variants in PTPN22 and CTLA4 Are Associated With ME/CFS With Infectious Onset. Front Immunol. 2020 Apr 9;11:578. doi: 10.3389/fimmu.2020.00578. eCollection 2020. https://www.ncbi.nlm.nih.gov/pubmed/32328064

Genetic Predisposition for Immune System, Hormone, and Metabolic Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Pilot Study

Abstract:

Introduction: Myalgic Encephalomyelitis/ Chronic Fatigue Syndrome (ME/CFS) is a multifactorial illness of unknown etiology with considerable social and economic impact. To investigate a putative genetic predisposition to ME/CFS we conducted genome-wide single-nucleotide polymorphism (SNP) analysis to identify possible variants.

Methods: 383 ME/CFS participants underwent DNA testing using the commercial company 23andMe. The deidentified genetic data was then filtered to include only non-synonymous and nonsense SNPs from exons and microRNAs, and SNPs close to splice sites. The frequencies of each SNP were calculated within our cohort and compared to frequencies from the Kaviar reference database. Functional annotation of pathway sets containing SNP genes with high frequency in ME/CFS was performed using over-representation analysis via ConsensusPathDB. Furthermore, these SNPs were also scored using the Combined Annotation Dependent Depletion (CADD) algorithm to gauge their deleteriousness.

Results: 5693 SNPs were found to have at least 10% frequency in at least one cohort (ME/CFS or reference) and at least two-fold absolute difference for ME/CFS. Functional analysis identified the majority of SNPs as related to immune system, hormone, metabolic, and extracellular matrix organization. CADD scoring identified 517 SNPs in these pathways that are among the 10% most deleteriousness substitutions to the human genome.

Source: Perez M, Jaundoo R, Hilton K, Del Alamo A, Gemayel K, Klimas NG, Craddock TJA, Nathanson L. Genetic Predisposition for Immune System, Hormone, and Metabolic Dysfunction in Myalgic Encephalomyelitis/Chronic Fatigue Syndrome: A Pilot Study. Front Pediatr. 2019 May 24;7:206. doi: 10.3389/fped.2019.00206. eCollection 2019. https://www.ncbi.nlm.nih.gov/pubmed/31179255