Prevalence of MEFV gene mutations in a large cohort of patients with suspected familial Mediterranean fever in Central Anatolia

Perinatal outcomes and long-term infectious morbidity of offspring born to mothers with familial Mediterranean fever

PURPOSE

To investigate perinatal outcomes and long-term infectious morbidity in children of mothers with familial Mediterranean fever (FMF).

METHODS

A population-based cohort study comparing perinatal outcomes and long-term infectious morbidity of offspring of mothers with and without FMF was conducted. All singleton deliveries between the years 1991-2021 in a tertiary medical center were included. The study groups were followed until 18 years of age for long-term infectious morbidity. A Kaplan-Meier survival curve was used to compare the cumulative incidence of long-term infectious morbidity, and generalized estimation equation (GEE) models as well as Cox proportional hazards models were constructed to control for confounders.

RESULTS

During the study period, 356,356 deliveries met the inclusion criteria. 411 of them were women with FMF. The mean follow-up period interval was 9.7 years (SD = 6.2) in both study groups. Using GEE models, preterm delivery, cesarean delivery, and low birth weight were independently associated with maternal FMF. The total infectious-related hospitalization rate was significantly higher in offspring born to mothers with FMF compared to the comparison group (Kaplan-Meier survival curve, log-rank p < 0.001). Using a Cox proportional hazards model, controlling for gestational age, maternal age, diabetes mellitus, cesarean delivery, and hypertensive disorders, being born to a mother with FMF was found to be an independent risk factor for long-term infection-related hospitalization of the offspring.

CONCLUSION

Maternal FMF was found to be independently associated with long-term infection-related hospitalization of the offspring. This positive correlation may reflect an intra-uterine pro-inflammatory environment which may result in the offspring's long-term susceptibility to infection.

Molecular analyses of MEFV gene mutation variants in Turkish population

BACKGROUND

Familial Mediterranean fever (FMF) is an autosomal recessive autoinflammatory disease primarily affecting individuals of Turkish, Armenian, Arab, and non-Ashkenazi Jewish descent, caused by mutations in the MEFV gene. The aim of this study was to review the common genotype distributions of MEFV variants and mutations in the Turkish population and evaluate rare mutations.

METHODS AND RESULTS

The study included 2984 patients who applied to Ankara University Ibni Sina Hospital Immunology Laboratory with clinical suspicion of FMF between 2004 and 2014. The data of patients from different regions of the country who were followed up in the immunology-rheumatology clinic with clinical suspicion and presumptive diagnosis of FMF were evaluated retrospectively. Patients were tested for all mutations in Exon 2 and Exon 10, including M694V, M680I, M694I, V726A, E148Q and R202Q. There were 2504 patients with FMF variant. According to genotyping, R202Q (n = 1567, 39.2%) was the most common mutation. The most common co-variant was the R202Q/M694V genotype (n = 507, 16.98%). Allele frequencies for MEFV mutations were as follows: R202Q (n = 1567, 39.2%), M694V (n = 1004, 25.1%), E148Q (n = 463, 11.5%), M680I (n = 354, 8.8%), V726A (n = 319, 7.9%), A744S (n = 51, 1.2%), R761H (N = 41, 1.0%), P706P (N = 25, 0.6%), E167D (N = 23, 0.5%), M694I (N = 23, 0.5%), and K695R (N = 20, 0.5%).

CONCLUSION

This research revealed the prevalence of both common and rare MEFV gene mutations in Turkish FMF patients in various age groups. R202Q was the most prevalent mutation.

Co-occurrence of familial Mediterranean fever with systemic lupus erythematosus in South Asian population

BACKGROUND AND OBJECTIVE

Familial Mediterranean fever (FMF) and systemic lupus erythematosus (SLE) are autosomal recessive auto-inflammatory diseases, triggered by FMF-associated gene mutations and auto-antigens. The literature on the co-occurrence of these two disorders is limited to case reports and their correlation is considered rare. We investigated the proportion of FMF among SLE patients when compared with a healthy adult cohort in South Asia.

METHODS

For this observational study, data from our institutional database were collected for the patients diagnosed with SLE. The control group was randomly selected from the database and were age- matched for SLE. The overall proportion of FMF among patients with and without SLE was considered. Student's t-test, Chi-square, and ANOVA were used for univariate analysis.

RESULTS

The study population included 3623 SLE patients and 14,492 controls. In the SLE group, there was a significantly higher proportion of FMF patients compared with the non-SLE group (1.29% vs. 0.79% respectively; p=0.015). SLE was prevalent in Pashtun's (50%) in the middle socioeconomic group while FMF was dominant in Punjabi's and Sindhi's (53%) in the low socioeconomic class.

CONCLUSION

This investigation demonstrates that FMF is more prevalent in a South-Asian population cohort of SLE patients.

MEFV gene allele frequency and genotype distribution in 3230 patients' analyses by next generation sequencing methods

Familial Mediterranean Fever (FMF, OMIM ID: 249100) is the most common autoinflammatory, autosomal recessive disease caused by mutations in the MEFV gene. It is widespread in the Mediterranean, primarily among Turkish, Armenian, Arab and Jewish. This study aims to examine genotype distributions of common MEFV variants in the Turkish population using targeted NGS and to evaluate all rare mutations. It included 3230 people applying to Ege University Children's Hospital Molecular Medicine Laboratory with the suspicion of autoinflammatory disease between 2017 and 2021. MEFV missense variant was detected in 1839 (56.9%) individuals. One or more mutations were found in them. 1063 patients were heterozygous (57.8%), 410 were compound heterozygous (22.3%), 238 were complex genotype (12.9%), and 128 were homozygous (7%). 56 different mutations and 141 genotypes were detected, two of which were novel (p.His87Arg, c.260A > G and p.Leu396Phe, c.1186C > T). These were determined as 6benign, 40 uncertain significant, 3 likely pathogenic and 7 pathogenic according to the ACMG classification. The most common ones were R202Q (n = 1097, 37.48%), E148Q (n = 512, 17.49%), M694V (n = 493, 16.84%), V726A (n = 155, 5.30%), M680I (n = 150, 5.12%), P369S (n = 108, 3.69%), R408Q (n = 95, 3.25%) respectively. They constitute 89.17 % of the entire patient population. In conclusion, DNA variants/mutations in the MEFV gene were evaluated in 3230 patients. To date, no mutation screening has been encountered in such a large population using NGS. Genotype distributions of both common and rare mutations were revealed. The obtained data will hopefully contribute to the future genotype-phenotype studies of FMF disease.

Clinical and molecular evaluation of MEFV gene variants in the Turkish population: a study by the National Genetics Consortium

Familial Mediterranean fever (FMF) is a monogenic autoinflammatory disorder with recurrent fever, abdominal pain, serositis, articular manifestations, erysipelas-like erythema, and renal complications as its main features. Caused by the mutations in the MEditerranean FeVer (MEFV) gene, it mainly affects people of Mediterranean descent with a higher incidence in the Turkish, Jewish, Arabic, and Armenian populations. As our understanding of FMF improves, it becomes clearer that we are facing with a more complex picture of FMF with respect to its pathogenesis, penetrance, variant type (gain-of-function vs. loss-of-function), and inheritance. In this study, MEFV gene analysis results and clinical findings of 27,504 patients from 35 universities and institutions in Turkey and Northern Cyprus are combined in an effort to provide a better insight into the genotype-phenotype correlation and how a specific variant contributes to certain clinical findings in FMF patients. Our results may help better understand this complex disease and how the genotype may sometimes contribute to phenotype. Unlike many studies in the literature, our study investigated a broader symptomatic spectrum and the relationship between the genotype and phenotype data. In this sense, we aimed to guide all clinicians and academicians who work in this field to better establish a comprehensive data set for the patients. One of the biggest messages of our study is that lack of uniformity in some clinical and demographic data of participants may become an obstacle in approaching FMF patients and understanding this complex disease.

Clinical significance of MEFV gene variation R202Q

BACKGROUND

The aim of this study was to evaluate the phenotypic features and the clinical significance of the R202Q mutation of the MEFV gene.

METHODS

We retrospectively reviewed the medical records of Familial Mediterranean Fever patients with M694V/- and M694V/R202Q mutations. We compared the patients regarding disease severity, symptoms, age at the onset of symptoms, gender, consanguinity, and family history.

RESULTS

Twenty-one patients (9 males, 12 females) had compound heterozygote mutation (M694V/R202Q), and 37 patients (23 males, 14 females) had M694V/- mutation. The mean age of the patients at the time of diagnosis was 7.3 ± 4.3 and 9.2 ± 3.7 years. The rate of arthritis was significantly higher in patients with M694V/R202Q heterozygote mutation than those with M694V/- heterozygote mutation (76.2% vs 32.4%; p =  < 0.001). The mean severity score was higher in M694V/R202Q heterozygote group although it did not reach statistical significance (8.43 ± 1.69 vs 7.49 ± 1.50; p = 0.082). However, the rate of having a high severity score was significantly higher in the M694V/R202Q mutation group than in the other group (47.6% vs 21.6%, respectively; p = 0.039). The rate of arthritis was significantly higher in patients with M694V/R202Q heterozygote mutation than those with M694V/- heterozygote mutation (76.2% vs 32.4%; p =  < 0.001).

CONCLUSION

Our finding supports the possibility that R202Q may be pathogenic rather than a variation. We found that the R202Q mutation is associated with the inflammatory phenotype of FMF; hence, the typical clinical findings of FMF especially arthritis can be observed in patients with compound mutation including R202Q. Key Points • We found that the R202Q mutation is associated with the inflammatory phenotype of FMF • The patients with the R202Q mutation had a greater rate of arthritis symptoms.

Familial coexistence of demyelinating diseases and familial Mediterranean fever

Familial Mediterranean fever (FMF) is a monogenic autoinflammatory disease characterized by fever and serositis attacks caused by mutations in the MEditerranean FeVer (MEFV) gene encoding the pyrin gene. Gain of the function mutations of the pyrin gene lead to stimulation of pro-inflammatory cytokines. Persistent pro-inflammatory situation in the course of FMF may play a role in the development of some other inflammatory diseases such as Behcet's disease, psoriasis, and vasculitis. Multiple sclerosis (MS), as a demyelinating disorder, is also more commonly seen in FMF patients compared to the general population. There are scarcely any research reporting that these two diseases coexist in more than one person in the same family. We have discovered cases of FMF and demyelinating disorders in five members of two different families. Besides the two families we are reporting, there are only four other families reported so far. Having combined the data of all these six families, we present a case-based review in this study. We aimed to draw attention of physicians to familial co-occurence of FMF and demyelinating disorders and also to discuss possible mechanisms of the coexistence of these two diseases in light of the literature.

Familial Mediterranean Fever and Asthma

OBJECTIVE

To assess the association between familial Mediterranean fever and asthma.

METHODS

This study was designed as a cross-sectional study. All patients diagnosed with familial Mediterranean fever between January 1, 2000, to December 31, 2016, who were prescribed colchicine were included in the study. Controls were matched by sex, date of birth, residential socioeconomic status, and country of birth. Logistic regression models were used to determine the odds ratio for asthma in familial Mediterranean fever patients and controls.

RESULTS

A total of 7,098 familial Mediterranean fever patients who were prescribed colchicine were identified. Of them, 3,547 (50%) were females, 3,632 (51%) were of low residential socioeconomic status and 6,160 (87%) were born in Israel. Their median age at the end of follow-up was 37 years (23-54). In an unadjusted logistic regression, familial Mediterranean fever was associated with asthma (OR = 1.33, 95%CI 1.17-1.51; p < 0.001). The association persisted after adjusting for sex, socioeconomic status, and country of birth (OR = 1.33, 95%CI 1.18-1.52; p < 0.001).

CONCLUSIONS

Familial Mediterranean fever is positively associated with asthma. Further research is required to validate our results and explore possible explanations of this association. These findings cast doubt on previous studies implying familial Mediterranean fever to be a protective factor from asthma.

Differential mutational profiles of familial Mediterranean fever in North Africa

Familial Mediterranean fever (FMF) is a recessive autoinflammatory disease, mainly occurring in the eastern Mediterranean. In these populations, the five FMF founder mutations are differently distributed. In Algeria, the FMF-causing variants remain poorly explored. This retrospective study aims to report the mutational profile of Algerian FMF patients and to compare it with North African FMF patients. One hundred eighty-three unrelated patients clinically suspected of FMF were recruited from various Algerian hospitals (2007-2015) and tested for mutations in exon 10 of MEFV gene. Molecular analysis identified 144 mutant alleles among 87 of 183 patients (47.5%). p.M694I was the most prevalent pathogenic allele, accounting for 63.2% of mutant alleles, followed by p.M694V and p.M680I occurring with a same frequency (14.5%). Others, p.A744S (6.2%) and p.I692del (1.3%), are less frequent. Interestingly, p.M694I was the most recurrent in patients with renal AA-amyloidosis. Our results provide the first genetic data on FMF in Algeria, demonstrating the predominance of p.M694I and the absence of p.V726A, compared to other North African countries (Morocco, Tunisia, and Egypt). In conclusion, North African FMF patients display differential mutational profiles that may result from the difference in ethnic origin and the genetic heterogeneity among these populations.