Familial Mediterranean fever (FMF) mutations occur frequently in the Greek-Cypriot population of Cyprus

Inherited metabolic disorders in Cyprus

Selective screening for inherited metabolic disorders (IMD) began in Cyprus in 1990. Over the last thirty-three years 7388 patients were investigated for IMD and 200 diagnoses were made (diagnostic yield 2.7%). The existence of a single laboratory of Biochemical Genetics for the whole island facilitated the creation of a national registry for IMD. The minimal prevalence of IMD in Cyprus is 53.3 cases per 100,000 live births. The most common group are disorders of amino acid metabolism (41.0%), followed by disorders of carbohydrate metabolism (16.5%), disorders of complex molecule degradation (16.5%), mitochondrial disorders (10.5%) and disorders of vitamin and co-factor metabolism (5.5%). Hyperphenylalaninaemia is the most common IMD (14.0%) followed by galactosaemia (7.0%), glutaric aciduria type I (5.5%) and MSUD (4.0%). Some disorders were found to have a relatively high incidence in specific communities, for example Sandhoff disease among the Cypriot Maronites and GM1 gangliosidosis in one particular area of the island. Other disorders were found to have a relatively higher overall incidence, compared to other Caucasian populations, for example galactosaemia, glutaric aciduria type I and MSUD, while fatty acid oxidation defects, Gaucher disease and classic PKU were found to have a relatively lower incidence. Molecular characterization of selected disorders revealed many novel genetic variants, specific to the Cypriot population.

Cardiovascular Sequelae and Genetics of Familial Mediterranean Fever: A Literature Review

INTRODUCTION

Familial Mediterranean fever (FMF) is an autoinflammatory fever syndrome distinguished by recurrent attacks of spontaneous peritonitis, pleuritis, fever, and arthritis. It is specifically seen in the ethnic groups of Mediterranean origin, but sporadic cases have been reported in Eastern Europe and America due to migrations. There is a number of cardiac manifestations associated with FMF.

METHODS

Using PubMed as the search engine, the literature search was done for articles published between 1958 and 2020. To summarize the body of available evidence, a scoping review was carried out to find relevant articles and case reports in patients of FMF with cardiovascular manifestations.

RESULTS

In the literature, there is a number of mechanisms explaining the cause of cardiac involvement in FMF, including the subclinical inflammation and secondary (AA) amyloid deposition in the vessels and the myocardium. There is a variable and often spurious course of these manifestations and it can be associated with a poor prognosis such as an acute myocardial infarction. In FMF patients, polyarteritis nodosa and Henoch-Schönlein purpura are seen more significantly as compared to the general population with increased frequency of mutations in Mediterranean fever (MEFV) gene. Through unclear mechanisms, Behçet's disease is associated with MEFV gene mutations and shares vascular manifestations with FMF. There is an interplay of IL-1 and MEFV gene, which impart an important role in inflammatory attacks of FMF. There is an intima-media thickening of blood vessels AA to persistent inflammation which can lead to atherosclerotic plaque formation resulting in atherosclerotic cardiovascular disease.

CONCLUSION

FMF and its associated cardiovascular diseases are interlinked to 2 main mechanisms: subclinical atherosclerosis and amyloid deposition, and colchicine is the primary treatment of patients with FMF which shows the regression of amyloid deposits and prevents cardiovascular sequelae.

Molecular Patterns of MEFV Gene Mutations in Egyptian Patients with Familial Mediterranean Fever: A Retrospective Cohort Study

Background

Familial Mediterranean Fever (FMF) is a hereditary autosomal recessive disease which is mainly seen in the Turks, Armenians, Arabs, and Jews. It is characterized by recurrent episodes of fever, polyserositis, and rash. MEFV gene, encoding pyrin protein, is located on the short arm of chromosome 16. FMF is associated with a broad mutational spectrum in this gene. Certain mutations are more common in particular ethnic groups. To date, different mutations of MEFV were observed in studies carried out in different regions worldwide. However, most of these studies did not extensively investigate the Egyptian population, in spite of the high prevalence of FMF in this geographical region.

Aim

To identify the frequency of MEFV gene mutations among the patients who presented with FMF like symptoms and, to characterize the different genetic mutations and their association with increased Amyloid A among Egyptian patients.

Methods

FMF Strip Assay (Vienna Lab Diagnostics, Vienna, Austria) was used. This test is based on reverse hybridization of biotinylated PCR products on immobilized oligonucleotides for mutations and controls in a parallel array of allele-specific oligonucleotides.

Results

Among the 1387 patients presenting with signs and symptoms suggestive of FMF, 793 (57.2%) were of undefined mutations, whereas 594 had MEFV gene mutations. 363 patients (26.2%) were heterozygous mutants, 175 patients (12.6%) were compound heterozygous mutants, and 56 patients (4%) were homozygous mutants. The most commonly encountered gene mutations in heterozygous and homozygous groups were E148Q (38.6%), M694I (18.1%), and V726A (15.8%). The most commonly encountered gene mutations in the compound heterozygous groups were E148Q+M694I observed in 20.6% of the patients, followed by M694I+V726A and M6801+V726A found in 18.9% and 11.4 %, respectively. The most commonly encountered gene mutation associated with abdominal pain, fever, and high serum Amyloid A was E148Q allele (37.5%).

Conclusions

Unlike all previous publications, E148Q allele was found to be the most frequent in the studied patients. Moreover, this allele was associated with increased Amyloid A. 793 patients were free of the 12 studied Mediterranean mutations, which implies the necessity to perform future sequencing studies to reveal other mutations.

Digenic inheritance and genetic modifiers

Digenic inheritance (DI) concerns pathologies with the simplest form of multigenic etiology, implicating more than 1 gene (and perhaps the environment). True DI is when biallelic or even triallelic mutations in 2 distinct genes, in cis or in trans, are necessary and sufficient to cause pathology with a defined diagnosis. In true DI, a heterozygous mutation in each of 2 genes alone is not associated with a recognizable phenotype. Well-documented diseases with true DI are so far rare and follow non-Mendelian inheritance. DI is also encountered when by serendipity, pathogenic mutations responsible for 2 distinct disease entities are co-inherited, leading to a mixed phenotype. Also, we can consider many true monogenic Mendelian conditions, which show impressively broad spectrum of phenotypes due to pseudo-DI, as a result of co-inheriting genetic modifiers (GMs). I am herewith reviewing examples of GM and embark on presenting some recent notable examples of true DI, with wider discussion of the literature. Undeniably, the advent of high throughput sequencing is bound to unravel more patients suffering with true DI conditions and elucidate many important GM, thus impacting precision medicine.

The MEFV gene pathogenic variants and phenotype-genotype correlation in children with familial Mediterranean fever in the Çanakkale population

The aim of the current study was to determine the frequency of the Mediterranean fever (MEFV) gene pathogenic variants in 60 children diagnosed with familial Mediterranean fever (FMF) and to compare the phenotype-genotype correlation. Genomic DNA was isolated by the spin-column method from peripheral blood samples (collected in vacutainers containing EDTA) and buccal smears. The MEFV gene profiles for the current FMF cohort were genotyped by pyrosequencing and direct Sanger sequencing techniques for the target pathogenic variants. The most prominent clinical symptoms were abdominal pain (53.4%), fever (23.4%) and arthritis (23.3%). Eighteen different pathogenic variants were identified and the most frequent were p.Met694Val (20.0%), p.Glu148Gln (13.3%), p.Met680 Ile (11.7%) and p.Arg202Gln (11.7%). Abdominal pain, fever and arthritis were the most common presenting clinical characteristics. Results showed that not only clinical characteristics, but also genotyping of the MEFV gene is needed to establish the correct diagnosis of FMF in children and other family members.

Severe liver involvement in two patients with long-term history of fever: remember familial Mediterranean fever

Familial Mediterranean fever (FMF) is characterised by recurrent, self-limited fever attacks and serositis. Severe liver involvement has rarely been reported. We present two FMF cases of a 55-year-old man and a 20-year-old woman in whom the prevailing manifestations were recurrent unexplained episodes of anicteric hepatitis (man) and recurrent severe jaundice (woman). A long-term history of recurrent self-limited episodes of fever was also claimed in both. After exclusion of infectious, malignant, autoimmune, and liver and biliary diseases, a diagnosis of FMF as confirmed by molecular analysis was established. The patients started colchicine 1 mg/day with immediate resolution of symptoms. During follow-up, no new episodes of fever and exacerbation of liver biochemical parameters have been recorded for 5 and 1 years. Physicians must keep FMF in mind in patients with recurrent episodes of unexplained severe liver impairment and fever and especially in regions like Mediterranean basin where hereditary periodic fever syndromes are common.

Prevalence of Mediterranean FeVer Gene Mutations in Turkish Cypriot Population

Objectives

This study aims to determine the carrier frequency and the most common mutations of the Mediterranean FeVer (MEFV) gene in healthy Cypriot population of Turkish origin.

Patients and methods

A total of 296 healthy participants (102 males, 194 females; median age 30 years; range 1 to 81 years) were evaluated. The exon 2, 3, 5 and 10 of MEFV genes were amplified by polymerase chain reaction.

Results

The participants demonstrated an extremely high carrier rate (12.5%). Most commonly detected mutations were E148Q and A74S, with rates of 7.3% and 2.8%, respectively.

Conclusion

Mediterranean FeVer gene mutation types and carrier rates in Turkish Cypriot population are different than other Mediterranean populations in the region. MEFV mutation carriage is frequent in North Cyprus and familial Mediterranean fever might be one of the causes for end stage renal disease in Turkish Cypriots.

Molecular and Clinical Investigation of Cystinuria in the Greek-Cypriot Population

BACKGROUND AND AIMS

Cystinuria represents 3% of nephrolithiasis in humans. Two genes have been identified as the main genetic causes of cystinuria, SLC3A1 and SLC7A9, with an autosomal recessive mode of inheritance. In the present study, we studied for the first time, genetically and clinically, all the cystinuric families identified so far in the Greek-Cypriot population.

METHODS

Discovery of mutations was performed through polymerase chain reaction (PCR)-single analysis and DNA resequencing. New families were investigated through PCR-RFLPs. Clinical data were collected through the hospital patients' records and analytical follow-up of the families.

RESULTS AND DISCUSSION

We found a total of five mutations in 28 Greek-Cypriot cystinuric patients belonging in 12 families. The most frequent mutation among the 28 Greek-Cypriot patients is the SLC3A1-p.T216M, which is also the second most frequent mutation in Europe, representing a genetic founder effect. Sixteen of the 28 patients are homozygous for this mutation. Even though a consanguinity loop was obvious in only one family, other patients were from families in small villages where endogamy was practiced for many centuries. Timely clinical and genetic diagnosis, accompanied by early treatment, is significant for the good health of most of our patients. Only ∼14% of them developed chronic renal failure, and only one reached end-stage renal disease (ESRD).

CONCLUSION

Five SLC3A1 and SLC7A9 mutations appear to be responsible for the genetic basis of cystinuria in the Greek-Cypriot patients; having such a limited number of causative mutations will simplify diagnostics for this population.

Near East University Genetic Mutation Database (NEU-GD): The first mutation database of Northern Cyprus

The health care system is negatively affected by the genetic disorders that lead to an increasing rate of morbidity and neonatal deaths and affect adults as well. These create a substantial government's psychosocial and economic burden on clinicians, patients and their families with the advancement in the field of genetics. There has been a tremendous increase in the rate in which diseases associated with variant DNA sequences are being sought and identified. The goal behind the creation of Near East University Genetic Mutation Database (NEU-GD) is to map and apprehend the patterns of common genetic diversity in the human genetic makeup in order to accelerate the search for the genetic causes of human disease. NEU-GD will allow scientists to generate extraordinarily useful information such as allelic variations among population, and description of the genetic blueprint of mutations occurring in human beings. In this communication we report the construction of the first genetic mutation database for the people belonging to different ethnic groups living in North Cyprus (http://genetics-db.neu.edu.tr/). Therefore NEU-GD can serve as an important tool available online for molecular genetic testing of inherited disorder and persuade for further investigation of novel genetic disorders in North Cyprus population.

Frequency of MEFV gene mutations in Hatay province, Mediterranean region of Turkey and report of a novel missense mutation (I247V)

In the present study, 1000 patients with clinical suspicion of FMF were retrospectively reviewed to determine the spectrum of MEFV gene mutations by using DNA sequence analysis between September, 2008 and April, 2012. Sixteen different mutations and 55 different genotypes were detected in 618 of 1000 patients. Among 16 different mutations, R202Q (21.35%) was the most frequently observed mutation; followed by E148Q (8.85%), M694V (7.95%), M680I (2.40%), V726A (1.85%), M694I (0.95%), A744S (0.80%), R761H (0.55%), P283L (0.35%), K695R (0.20%), E230K (0.15%), L110P (0.10%), I247V (0.05%), G196W (0.05%) and G304R (0.05%). In the present study, a novel missense mutation (I247V) and a silent variant (G150G) were identified in the MEFV gene. On the other hand, P238L, G632A and G304R mutations are the first cases reported from Turkey. Our results indicated that MEFV mutations are highly heterogeneous in our study population as in other regions of Turkey and mutation screening techniques such as PCR-RFLP, amplification refractory mutation system or reverse hybridization do not adequately detect uncommon or novel mutations. Therefore, it was proven that sequence analysis of the MEFV gene could be useful for detection of rare or unknown mutations.

Familial Mediterranean fever: An updated review

Familial Mediterranean Fever (FMF) is a hereditary autoinflammatory disorder characterised by acute attacks of fever and serosal inflammation. FMF primarily affects Jewish, Armenian, Turkish, and Arab populations. The disease is accompanied by a marked decrease in quality of life due to the effects of attacks and subclinical inflammation in the attack-free periods. Untreated or inadequately treated patients run the risk of amyloidosis, which is an important cause of morbidity and mortality. In this review, the current information available on FMF is summarised.

Incidence of end-stage renal disease in the Turkish-Cypriot population of Northern Cyprus: a population based study

BACKGROUND

This is the first report of the incidence and causes of end-stage renal disease (ESRD) of the Turkish-Cypriot population in Northern Cyprus.

METHODS

Data were collected over eight consecutive years (2004-2011) from all those starting renal replacement therapy (RRT) in this population. Crude and age-standardised incidence at 90 days was calculated and comparisons made with other national registries. We collected DNA from the entire prevalent population. As an initial experiment we looked for two genetic causes of ESRD that have been reported in Greek Cypriots.

RESULTS

Crude and age-standardised incidence at 90 days was 234 and 327 per million population (pmp) per year, respectively. The mean age was 63, and 62% were male. The age-adjusted prevalence of RRT in Turkish-Cypriots was 1543 pmp on 01/01/2011. The incidence of RRT is higher than other countries reporting to the European Renal Association - European Dialysis and Transplant Association, with the exception of Turkey. Diabetes is a major cause of ESRD in those under 65, accounting for 36% of incident cases followed by 30% with uncertain aetiology. 18% of the incident population had a family history of ESRD. We identified two families with thin basement membrane nephropathy caused by a mutation in COL4A3, but no new cases of CFHR5 nephropathy.

CONCLUSIONS

This study provides the first estimate of RRT incidence in the Turkish-Cypriot population, describes the contribution of different underlying diagnoses to ESRD, and provides a basis for healthcare policy planning.

Hereditäre Fiebersyndrome

Das familiäre Mittelmeerfieber (FMF), Hyper-IgD-Syndrom (HIDS) und das Tumornekrosefaktor(TNF)-Rezeptor-1-assoziierte periodische Syndrom (TRAPS) sind monogene Krankheiten, die unter dem Begriff der hereditären Fiebersyndrome zusammengefasst werden. Sie sind durch rezidivierende Episoden mit Fieber und Entzündungszeichen gekennzeichnet und werden von Mutationen in Genen verursacht, denen eine Funktion bei der angeborenen Immunität zukommt. Die vorliegende Übersichtsarbeit befasst sich mit dem klinischen Erscheinungsbild und der Genetik der hereditären Fiebersyndrome. Sie sind für die humangenetische Beratung von Bedeutung.

[Molecular diagnostics of hereditary fever syndromes. Familial Mediterranean fever (FMF), hyperimmunoglobulin D syndrome (HIDS), tumor necrosis factor receptor-associated periodic syndrome (TRAPS), cryopyrin-associated periodic syndrome (CAPS: FCAS, MWS, NOMID/CINCA)]

Periodic episodes of fever and inflammation can have a genetic origin. Nowadays, the identification of the causative genetic variants in the majority of cases allows molecular genetic confirmation of the clinical diagnosis, which enables approaches with specific drug treatment and improves patient compliance as well as genetic counseling. Besides a detailed clinical examination a medical history including family history and an assessment of the ethnic origin are required. In order to make genetic testing straightforward and cost effective an iterative procedure should be followed which should include, in addition to clinical data, the frequencies of causative mutations in the various gene segments involved.

Screening for Familial Mediterranean Fever M694V and V726A mutations in the Greek population

Familial Mediterranean Fever (FMF) is an autosomal recessive genetic disease that primarily affects populations surrounding the Mediterranean basin. FMF patients suffer from recurrent episodes of fever accompanied by abdominal pain, pleuritis, and arthritis. Missense mutations in the gene for FMF (MEFV) have been shown to be responsible for the disease, while more than 70 mutations have been identified to date. The aim of the present study was to determine the carrier rates of two of the most common MEFV mutations, M694V and V726A, in the general Greek population. A cohort of 220 healthy and unrelated individuals of Greek descent was screened for the two MEFV mutations using the Amplification Refractory Mutation System. Our results showed that none of the healthy individuals tested were carriers of any of the two mutations. In conclusion, our study independently confirms that the carrier rate for the MEFV mutations M694V and V726A is extremely low in the general Greek population.

Dysregulation of innate immunity: hereditary periodic fever syndromes

The hereditary periodic fever syndromes encompass a rare group of diseases that have lifelong recurrent episodes of inflammatory symptoms and an acute phase response in common. Clinical presentation can mimic that of lymphoproliferative disorders and patients often go undiagnosed for many years. These syndromes follow an autosomal inheritance pattern, and the major syndromes are linked to specific genes, most of which are involved in regulation of the innate immune response through pathways of apoptosis, nuclear factor kappaBeta activation and cytokine production. In others, the link between the protein involved and inflammation is less clear. The recurrent inflammation can lead to complications, such as renal impairment due to amyloidosis and vasculitis, visual impairment, hearing loss, and joint destruction, depending on the specific syndrome. In recent years, treatment options for these diseases have improved significantly. Early establishment of an accurate diagnosis and start of appropriate therapy improves prognosis in these patients.

Population genetics of familial Mediterranean fever: a review

In this review, some principal population genetic features of familial Mediterranean fever (FMF) are considered. These relate to the time and the place of founder mutations' origins, the role of ancient migrations and contacts between populations in the spatial spreading of the disorder, the influence of environmental factors and cultural traditions on the rate of FMF incidence, and possible selective advantage in carriers of FMF causing gene (MEFV) mutations.

MEFV alterations and population genetics analysis in a large cohort of Greek patients with familial Mediterranean fever

Familial Mediterranean fever (FMF) is a disease characterized by recurrent, self-limiting bouts of fever and serositis and caused by altered pyrin due to mutated MEFV gene. FMF is common in the Mediterranean Basin populations, although with varying genetic patterns. The spectrum and clinical significance of MEFV alterations in Greece has yet not been elucidated. The aim of this study was to analyze the spectrum of MEFV alterations in FMF patients and healthy individuals in Greece. A cohort of 152 Greek FMF patients along with 140 Greek healthy controls was enrolled. Non-isotopic RNase cleavage assay (NIRCA) and sequencing allowed mutational and haplotypic analysis of the entire coding sequence of MEFV. The ARLEQUIN 2.0, DNASP 4.0 and PHYLIP software were used for population genetics analysis. Among patients, 127 (83.6%) carried at least one known mutation. The most common mutations identified were M694V (38.1%), M680I (19.7%), V726A (12.2%), E148Q (10.9%) and E230K (6.1%). The total carrier rate among healthy individuals was 0.7%. The presence of R202Q homozygosity in 12 of the remaining 25 MEFV negative FMF patients might be considered as disease related in Greeks. Population genetics analysis revealed that Greeks rely closer to the eastern rather than western populations of the Mediterranean Basin.

Mutational analysis of the PRYSPRY domain of pyrin and implications for familial mediterranean fever (FMF)

Familial Mediterranean fever (FMF) is an autosomal, recessively inherited disease, characterized by recurrent fever and serositis that affects mainly patients of the Mediterranean basin. The gene responsible for FMF, named MEFV, was cloned and several missense mutations were found to be responsible for the disease. Based on a recent molecular analysis of MEFV gene mutations in 43 patients from Crete aiming to correlate specific genotypes and clinical manifestations of FMF, we were prompted to construct a three-dimensional model (3-D model) of the PRYSPRY domain of pyrin. The majority of the known MEFV mutations located on this domain have been classified, according to disease severity, and localized on this 3-D model. The functional consequences of these mutations and their implications on disease severity are discussed. Moreover, we report a putative novel missense mutation, S702C, which we identified in exon 10 of the MEFV gene and localized on the constructed 3-D model.

Clinical and subclinical inflammation in patients with familial Mediterranean fever and in heterozygous carriers of MEFV mutations

OBJECTIVE

To prospectively monitor inflammatory activity over a prolonged period in a cohort of Turkish patients with FMF, their healthy relatives and healthy controls and to relate this to their MEFV genotypes.

METHODS

43 patients with FMF and 75 of their asymptomatic relatives underwent fortnightly assessments and venesection for measurement of CRP and SAA over 5 months. 50 unrelated healthy population matched controls were also studied. MEFV genotyping was performed on all participants and comparisons were made between the different groups.

RESULTS

Paired MEFV mutations were detected in 84% of FMF patients and single mutations in 12%. Substantial acute phase reactivity was seen among the patients with FMF during attacks (median SAA 693 mg/l, CRP 115 mg/l). Between attacks there was also some inflammatory activity (median SAA 6 mg/l, CRP 4 mg/l). Among healthy controls 16% were heterozygotes for MEFV mutations and 4% had two mutations. As expected there was a substantial carrier rate among healthy relatives with mutations detected in almost 92%. Asymptomatic MEFV heterozygotes had elevated acute phase proteins compared to wild type subjects.

CONCLUSION

Substantial sub-clinical inflammation occurs widely and over prolonged periods in patients with FMF, indicating that the relatively infrequent clinically overt attacks represent the 'tip of the iceberg' in this disorder. Both basal and peak acute phase protein concentrations were greater in MEFV heterozygotes than in wild-type controls, regardless of mutation demonstrating a 'pro-inflammatory' phenotype among FMF carriers. Upregulation of the acute phase response among carriers of FMF may augment their innate host response and contribute to better resistance to infection.

Familial Mediterranean Fever and E148Q Pyrin Gene Mutation in Greece

Familial Mediterranean fever (FMF) is an inherited disease characterized by recurrent inflammatory polyserositis. Although FMF is classically expected only in Middle East populations, it is becoming evident that the disease affects more groups than initially thought. The disease is associated with a number of mutations of the MEFV gene, which codes for a protein named pyrin. The role of E148Q pyrin gene mutation in the development of FMF remains inconclusive. Some authors believe it causes the disease, whereas others favor the concept of a noncausative role. To understand better the role of this mutation, gathering data from different populations may be of value. We studied 60 Greek cases fulfilling the criteria for FMF diagnosis, 30 cases being a definite FMF diagnosis and 30 a probable diagnosis. Twenty-one of the patients, carried mutation E148Q. One was a homozygote (E148Q/E148Q), and 20 carried mutation E148Q in combination with other mutations (compound heterozygotes). In 6 of the 60 cases studied, no mutations were found. Compared with the results for healthy controls, E148Q mutation is significantly frequent. Because different populations may exhibit different patterns of pyrin mutations, association of the E148Q mutation with FMF should be considered in connection with origin data.

Non-isotopic RNase cleavage assay for mutation detection in MEFV, the gene responsible for familial Mediterranean fever, in a cohort of Greek patients

BACKGROUND

The MEFV gene is responsible for familial Mediterranean fever (FMF). Several disease associated mutations have been identified. The range of genetic variation in MEFV in Greek patients has not been determined.

OBJECTIVE

To describe a method that facilitates the routine screening of the entire coding sequence of MEFV (excluding exon 1).

METHODS

The non-isotopic RNase cleavage assay (NIRCA) was optimised and used as a first step screening method to screen exons 2 to 10 of MEFV. Exons 2 and 10 were analysed separately at DNA level, while exons 3 to 9 were analysed together at cDNA level. The sample group consisted of 26 FMF patients diagnosed using established clinical criteria, six asymptomatic relatives, 12 patients with atypical clinical manifestations, nine patients suffering from various inflammatory diseases, and three normal individuals. All were analysed by NIRCA for mutations in the MEFV gene and direct sequencing was applied subsequently to confirm the results.

RESULTS

MEFV mutations were identified in 25 of 26 typical FMF patients and in two of 12 patients with atypical manifestations. NIRCA results were in concordance with sequencing findings in all sequences analysed, suggesting that the method is highly reliable in this disease. Sixteen alterations of MEFV were identified (eight missense mutations and eight single nucleotide polymorphisms).

CONCLUSIONS

NIRCA can be used for rapid screening of the coding sequence of the MEFV gene in patients suspected of suffering from FMF.

Familial Mediterranean fever is no longer a rare disease in Italy

Familial Mediterranean fever (FMF) is an autosomal recessive disorder, characterised by short, recurrent attacks of fever with abdominal, chest or joint pain and erysipelas-like erythema. It is an ethnically restricted genetic disease, found commonly among Mediterranean populations, as well as Armenians, Turks, Arabs and Jews. Traditionally, Italians have been considered little affected by FMF, despite the geographical position of Italy (northern Mediterranean basin) and the migratory changes in its population. The objective was to characterise the demographic, clinical and genetic features of FMF in Italy. Patients of Italian origin were recruited from those referred to Italian-French medical centres for FUO (Fever of Unknown Origin) or 'surgical' emergencies; clinical history, genealogy and physical examination were recorded; all other possible infectious, neoplastic, auto-immune and metabolic diseases were excluded. Mutational analysis of the gene responsible for FMF (MEFV on 16p13.3) was performed, after which geno-phenotypical correlations were established. Italian FMF patients, 40 women and 31 men, aged from 3 to 75 years, have shown all the clinical manifestations indicative of FMF described in the literature, but with a lower incidence of amyloidosis. The genetic tests have been contributive in 42% of cases. The frequency of each different mutation has been similar to that found in a series of 'endemic' countries. The geno-phenotypical correlations have suggested the existence of genetic and/or environmental modifier-factors. Among Italians FMF seems to be more frequent than was believed in the past. The data presented are consistent with their geographical location and their history.