MEFV-Mutationsspektrum bei familiärem Mittelmeerfieber (FMF)

Evidence for genetic overlap between adult onset Still's disease and hereditary periodic fever syndromes

OBJECTIVE

Adult onset Still's disease (AOSD) is a severe, autoimmune disease that can be challenging to treat with conventional therapeutics and biologicals in a considerable number of cases. Therefore, there is a high need to understand its pathogenesis better. As major clinical symptoms overlap between AOSD and hereditary periodic fever syndromes (HPFS), we analysed four known HPFS genes in AOSD.

METHODS

We performed Sanger sequencing and quantitative analysis of all coding regions of MEFV, TNFRSF1A, MVK and NLRP3 in 40 AOSD patients. All rare coding variants (n = 6) were evaluated for several aspects to classify them as benign to pathogenic variants. Statistical analysis was performed to analyse whether variants classified as (likely) pathogenic were associated with AOSD.

RESULTS

We identified three rare variants in MEFV, one previously not described. Association to the three likely pathogenic MEFV variants was significant (p _c = 2.34E- 03), and two of the three carriers had a severe course of disease. We observed strong evidence for significant association to mutations in TNFRSF1A (p _c = 2.40E- 04), as 5% of patients (2/40) carried a (likely) pathogenic variant in this gene. Both of them received a biological for treatment.

CONCLUSION

Our results indicate TNFRSF1A as a relevant gene in AOSD, especially in patients with a more challenging course of disease, while causal variants remain to be identified in the majority of patients.

R202Q/M694V as novel MEFV gene mutations in chronic periodontitis and familial Mediterranean fever

BACKGROUND AND OBJECTIVE

Familial Mediterranean fever (FMF) and chronic periodontitis are inflammatory diseases leading to an increase in the number of inflammasomes. To date, no published studies have reported on mutations in the Mediterranean fever (MEFV) gene in patients with chronic periodontitis, although the roles of MEFV gene mutations in FMF and FMF-associated amyloidosis (FMF-A) are well known. Therefore, the aim of this study was to evaluate the frequencies of MEFV gene mutations and serum amyloid A (SAA) and high-sensitivity C-reactive protein (hs-CRP) levels in patients with chronic periodontitis, FMF and FMF-A.

MATERIAL AND METHODS

The study population included 122 patients with FMF and 128 subjects who were systemically healthy. Clinical periodontal parameters, including the plaque index, gingival index, probing pocket depth, clinical attachment level and percentage of bleeding on probing were recorded. Blood samples were obtained from patients with FMF and systemically healthy controls, and all mutations located on exons 2 and 10 of the MEFV gene were analyzed by DNA Sanger Sequencing, which is the gold standard. SAA and high-sensitive CRP levels were also assessed.

RESULTS

Mean gingival index, percentage of bleeding on probing, probing pocket depth and clinical attachment level, and the levels of SAA and hs-CRP were higher in the FMF-A group than those in the FMF and control groups. The two most relevant mutations in patients with FMF were heterozygous M694V (46.2%), and heterozygous R202Q (32.7%). The frequencies of the homozygous M694V and R202Q mutations in the FMF-A group were 53.8% and 46.1%, respectively. The complex R202Q/M694V homozygous state led to an increased risk of chronic periodontitis (odds ratio: 3.6), and FMF-A (odds ratio: 7.6).

CONCLUSION

This is the first study to report the R202Q mutation in patients with periodontitis. Furthermore, the MEFV gene-mediated inflammatory pathway increased serum acute phase reactants, and the changes in the R202Q and M694V could play a role in inflammatory-genetic diseases, such as FMF, FMF-associated amyloidosis and chronic periodontitis.

Patient with FMF and Triple MEFV Gene Mutations

Introduction:

Familial Mediterranean fever (FMF) is the most common auto-inflammatory disease with monogenic (MEditerranean FeVer –MEFV- gene) inherited pattern. It mainly affects ethnic groups living along the eastern Mediterranean Sea: Turks, Sephardic Jews, Armenians, and Arabs [1]. Today FMF is not rare disease in other Mediterranean ethnicities, such as Greeks, Italians, and Iranians.

Case report:

Here we report a child with complex allele mutations E148Q/V726A/R761H, whilst, whose mother showed E148Q/V726A and his father had R761H/wt in analysis. The severity of the disease and genotype-phenotype correlation of patient showed no significant differences with his mother and other patients with the same two mutations, V726A/R761H, E148Q/V726A, and E148Q/R761H.

Conclusion:

This type of mutation is the first report of triple mutations in FMF patients with no specific phenotype correlation.

Phenotype-genotype updates from familial Mediterranean fever database registry of Mansoura University Children' Hospital, Mansoura, Egypt

BACKGROUND:

Familial Mediterranean fever (FMF) is autosomal recessive disease that affects people from Mediterranean region, Europe and Japan. Its gene (Mediterranean fever [MEFV]) has more than 100 mostly non-sense mutations.

OBJECTIVES:

The objective of the following study is to provide some phenotype-genotype correlates in FMF by categorizing the Egyptian FMF cases from Delta governorates after analysis of the four most common mutations of MEFV gene (M680I, M694I, M694V, V726A).

SUBJECTS AND METHODS:

Clinically, suspected FMF cases using Tel-Hashomer criteria were enrolled in the study. Cases were referred to Mansoura University Children's Hospital that serves most of the most middle Delta governorates, in the period from 2006 to 2011. Subjects included 282 males and 144 females, mean age of onset 9.3 ± 2.2 years. All cases were analyzed for these mutations using amplification refractory mutation system based on the polymerase chain reaction technique. Five FMF patients agreed to undergo renal biopsy to check for development of amyloidosis. Analysis of data was carried out using SPSS (SPSS, Inc., Chicago, IL, USA).

RESULTS:

Mutation was found in 521 out of 852 studies alleles, the most frequent is M694V (35.4%) followed by M694I, V726A and M680I. 11 cases were homozygous; 7 M694V, 3 M680I and only one M694I case. Severe abdominal pain occurred in 31 (7.28%) but severe arthritis in 103 cases (24.2%). Strong association was found between arthritis and homozygous mutant compared with single and double heterozygous (72.7% vs. 33.3% and 20.24%, P < 0.001). Four amyloid cases were M694V positive.

CONCLUSION:

M694V allele is the most common among Egyptian FMF especially those with amyloidosis. We recommend routine check for amyloidosis in FMF cases to statistically validate this link.

The frequency of Familial Mediterranean fever gene mutations and genotypes at Kirikkale and comparison with the mean of regional MEFV mutation frequency of Turkey

In this study we have retrospectively analysed the mutation spectrum of the 351 Familial Mediterranean fever patients referred to Kırıkkale University Faculty of Medicine, Department of Medical Genetics Laboratory over a period of 5 years and compared them with Turkey's mean. We have found 11 different mutations, including rare mutations such as F479L, K695R, M680I(G/A) and 45 different genotypes showing the heterogeneity of MEFV mutations in Central Anatolia. The most three prevalent mutations were M694V (14.8%), E148Q (7.1%) and M680I(G/C) (4.1%) in accordance with the literature. We have also investigated R202Q in our routine molecular diagnosis. Mutation causing R202Q (c.605G > A) change was described as a frequent polymorphism and G allele was found in linkage disequilibrium (LD) with M694V. There are limited number of studies investigating R202Q, some of them implicate that its homozygote state is disease causing. We showed the high frequency of R202Q (23.7%) with and without M694V in all the groups analysed and its high LD rate with M694V in the diagnosed group. Our study is reflecting the mutational heterogeneity of MEFV and summarize mutational spectrum of Turkey's geographical regions and overall Turkey.

Significance of MEFV gene R202Q polymorphism in Turkish familial Mediterranean fever patients

OBJECTIVE

Familial Mediterranean fever (FMF) is an autosomal recessive disorder characterized by recurrent attacks of fever and inflammation in the peritoneum, synovium, or pleura, accompanied by pain. The disease is associated with mutations in the Mediterranean fever (MEFV) gene, which encodes for the pyrin protein. The aim of this study was to explore the frequency and clinical significance of the R202Q (c.605G>A) polymorphism in exon 2 of the MEFV gene in a cohort of Turkish patients with FMF.

METHODS

The study included 191 patients with FMF and 150 healthy controls. Genomic DNA was isolated and genotyped using polymerase chain reaction (PCR)-based restriction fragment length polymorphism (RFLP) assay for the MEFV gene R202Q polymorphism.

RESULTS

The genotype and allele frequencies of R202Q polymorphism showed a statistically significant difference between FMF patients and controls (p<0.0001 and p=0.0004, respectively) and especially the homozygous AA genotype was significantly higher in FMF patients than healthy controls (p=0.0002; odds ratio=6.27; 95% CI=2.1-18.3). However no significant association was observed between clinical and demographic features of FMF patients and R202Qpolymorphism.

CONCLUSION

The results of this study showed that there was a high association between MEFV gene R202Q polymorphism and FMF. R202Q polymorphism should be included in routine molecular diagnosis of FMF patients.