Genotype Mutations in Egyptian Children with Familial Mediterranean Fever: Clinical Profile, and Response to Colchicine

Genotype Mutations in Palestinian Children with Familial Mediterranean Fever: Clinical Profile, and Response to Colchicine Treatment: A Retrospective Cohort Study

Background

Familial Mediterranean fever is a hereditary autoinflammatory disease affecting mainly Arabs, Turks, Armenians, and Jews with genotype-phenotype heterogeneity, presenting as recurrent episodes of fever along with polyserositis and rash. To date, more than 370 mutations in the MEFV gene have been recognized to cause the disease.

Methods

We conducted a retrospective cohort study involving 124 patients in Hebron, Palestine, diagnosed with FMF at the Al-Ahli, and Palestinian Red Crescent Society (PRCS) Hospitals.

Results

The median age of diagnosis was five years, presenting as abdominal pain (76.6%), fever (67.7%), joint pain and arthritis. Regarding MEFV gene mutations, we had 62 patients (50%) with heterozygous genotypes, 40 patients (32.3%) with homozygous phenotypes, 21 patients (16.9%) with compound heterozygous genotypes, and one was a missing state. Regarding variant frequencies, M694V was the most common one (43.4%), followed by E148Q (15.6%), V726A (5.7%), A744S (4.1%), and R202Q (4.1%). Positive family history was detected in 59 patients (54.6%), and there was no significant difference in zygosity regarding characteristics, consanguinity, and family history.

Conclusions

We affirm in this study of 124 children with FMF, abdominal pain, followed by fever, joint pain and arthritis were the main manifestations. Further, M694V, E148Q, V726A, A744S, and R202Q were the most frequent mutations, and carrying the M649V mutations is associated with a predisposition to other comorbidities. We believe that this study gives a pervasive overview of FMF in Palestinian patients. Looking forward, future studies on a larger number of patients could precisely highlight the genotype-phenotype association among FMF patients.

Juvenile-onset systemic lupus erythematosus and MEFV polymorphism: A case-control association study among Iranian children

INTRODUCTION AND OBJECTIVES

This study is designed to evaluate the potential influences of Mediterranean fever gene (MEFV) gene polymorphism on systemic lupus erythematosus (SLE) in a cohort of juvenile patients. A case-control study was performed on Iranian patients with a mixed ethnicity population.

PATIENTS AND METHODS

Genotypes of 50 juvenile cases, and 85 healthy controls were investigated for identifying M694V and R202Q polymorphism. Genotyping was done utilizing amplification refractory mutation system-polymerase chain reaction (ARMS-PCR) and polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) to detect M694V and R202Q mutations, respectively.

MAIN FINDINGS

Our study indicates significant differences in the alleles and genotypes frequencies of MEFV polymorphism between SLE patients and healthy controls (P<0.05). Also, an association was found between renal involvement (50% vs. 8.3%, P=0.000, OR=0.91, 95% CI=0.30-0.278) in juvenile SLE patients and M694V polymorphism incident; But there was no association with other clinical manifestations.

PRINCIPAL CONCLUSION

We found a significant association between R202Q and M694V polymorphism of the MEFV gene and susceptibility to SLE in the studied population; However, further studies on detailed characterization of these polymorphisms' impacts on the key elements responsible for SLE pathogenesis is of great importance.

Genetic and Epigenetic Regulation of MEFV Gene and Their Impact on Clinical Outcome in Auto-Inflammatory Familial Mediterranean Fever Patients

Epigenetic modifications play a pivotal role in autoimmune/inflammatory disorders and could establish a bridge between personalized medicine and disease epidemiological contexts. We sought to investigate the role of epigenetic modifications beside genetic alterations in the MEFV gene in familial Mediterranean fever (FMF). The study comprised 63 FMF patients diagnosed according to the Tel Hashomer criteria: 37 (58.7%) colchicine-responders, 26 (41.3%) non-responders, and 19 matched healthy controls. MEFV mutations were detected using a CE/IVD-labeled 4-230 FMF strip assay. DNA methylation of MEFV gene exon 2 was measured using bisulfite modification and related to pyrin level, phenotypic picture, MEFV mutations, disease severity, serum amyloid A (SAA), CRP, ESR, disease severity, and colchicine response. Our results showed that FMF patients exhibited significantly higher methylation percentage (p < 0.001) and lower pyrin levels (p < 0.001) compared to the control. The MEFV gene M694I mutation was the most commonly reported mutation (p < 0.004). High methylation percentage of the MEFV exon 2 and low pyrin concentration were correlated with disease severity, high SAA, ESR levels, H-pylori, and renal calculi. In conclusion, this study highlights the relation between high methylation percentage, reduced pyrin level, and different biomarkers in FMF, which underscores their role in the pathogenesis of FMF and could be considered as potential therapeutic targets.

Spectrum of MEFV gene mutations in 4,256 familial Mediterranean fever patients from Iran: a comprehensive systematic review

Background

Familial Mediterranean fever (FMF), known as a disease with a high prevalence rate among Armenian, Turkish, Jewish, and Arab descent populations, occurs as a result of pathogenic variants in mediterranean fever (MEFV) gene. The aim of this study was to review the spectrum and frequency of MEFV gene mutations reported among Iranian FMF patients.

Methods

After performing a systematic review of the literature and implementation of inclusion and exclusion criteria, 16 articles published between 2004 and 2020, involving 4,256 Iranian FMF patients, were included.

Results

A total of 38 different MEFV gene mutations were identified. The most common mutations among Iranian FMF patients were: p.M694V (c.2080A > G) (20.27%), p.E148Q (c.442G > C) (10.27%), p.V726A (c.2177T > C) (8.24%), p.M680I (both c.2040G > C and c.2040G > A) (7.20%), p.R761H (c.2282G > A) (2.1%), and p.M694I (c.2082G > A) (2. 1%). The frequencies of these mutations were significantly different in different parts of the country.

Conclusions

The ranks and frequencies of p.M694V, p.E148Q, p.V726A, p.M680I, and p.M694I in our population were closer to those observed in the Mediterranean countries, especially in the Middle Eastern Arab populations. Although some comprehensive studies have been performed on Azeri Turkish patients living in northwestern Iran, studies in other areas, especially in eastern Iran, have been very limited. One reason for this observation could be due to the low frequency of FMF patients in those areas. Regardless of the reason for this, the exact spectrum and frequency of MEFV gene mutations in Iranian FMF patients remain unclear. Therefore, comprehensive future studies in different parts of the country are recommended.

Founder variants and population genomes-Toward precision medicine

Human migration and community specific cultural practices have contributed to founder events and enrichment of the variants associated with genetic diseases. While many founder events in isolated populations have remained uncharacterized, the application of genomics in clinical settings as well as for population scale studies in the recent years have provided an unprecedented push towards identification of founder variants associated with human health and disease. The discovery and characterization of founder variants could have far reaching implications not only in understanding the history or genealogy of the disease, but also in implementing evidence based policies and genetic testing frameworks. This further enables precise diagnosis and prevention in an attempt towards precision medicine. This review provides an overview of founder variants along with methods and resources cataloging them. We have also discussed the public health implications and examples of prevalent disease associated founder variants in specific populations.

Toll-like receptor-4 gene variations in Egyptian children with familial Mediterranean fever

Background

Familial Mediterranean fever (FMF) is an autosomal recessive disorder affecting people in the region of the Mediterranean Sea. It is usually associated with mutation in Mediterranean fever (MEFV) gene that encodes the pyrin protein, which affects the innate inflammatory response. Toll-like receptors (TLR) are a family of pattern recognition receptors that recognize pathogenic microbes and activate antimicrobial defense mechanisms. Toll-like receptor 4 (TLR-4) is concerned with recognition of gram-negative organisms. There is growing clinical evidence suggesting a role for expression of TLRs in the immune pathogenesis of FMF. Thus, the aim of the current study was to evaluate the presence of TLR-4 (p.Asp299Gly) and TLR-4 (p.Thr399Ile) gene variants in association with Egyptian children having FMF, furthermore, its effect on disease course and severity.

Results

Seventy Egyptian children diagnosed as having FMF, together with 50 age and gender-matched controls were enrolled in the study. The TLR-4 (p.Asp299Gly) and (Thr399Ile) gene variants were determined by PCR-RFLP analysis for all studied patients and controls. TLR-4 p.Asp299Gly gene variant was detected in 1 (1.4%) of the patients and p.Thr399Ile gene variant was detected in 2 (2%). None of the controls had any of the two tested gene variants. All found variations were heterozygous. We could not find a statistically significant association with disease severity in cases with or without TLR-4 gene variants (P = 0.568). Patients with M694V gene mutation showed a higher disease severity (P = 0.035).

Conclusion

TLR-4 (p.Asp299Gly) and (p.Thr399Ile) gene variants were not found to have a link with the occurrence, the clinical picture of FMF, its severity, and response to colchicine treatment in Egyptian children. M694V gene mutation seems to be associated with higher disease severity. Further larger studies are needed to verify these results.