Amyloidosis in familial Mediterranean fever patients: correlation with MEFV genotype and SAA1 and MICA polymorphisms effects

BACKGROUND: Familial mediterranean fever (FMF) is a recessively inherited disease characterized by recurrent crises of fever, abdominal, articular and/or thoracic pain. The most severe complication is the development of renal amyloidosis. Over 35 mutations have been discovered so far in the gene responsible for the disease, MEFV. This article aims at determining a correlation between the MEFV genotype and the occurence of amyloidosis in FMF patients, in addition to the study of the modifying effects of the SAA1 (type 1 serum amyloid A protein) and MICA (Major Histocompatibility Complex (MHC) class-I-chain-related gene A) genes on this severe complication. METHODS: Fourteen MEFV mutations were screened and the SAA1 and MICA polymorphisms tested in 30 FMF patients with amyloidosis and 40 FMF patients without amyloidosis. RESULTS: The M694V and V726A allelic frequencies were, respectively, significantly higher and lower in the group with amyloidosis, compared to the control FMF group. The beta and gamma SAA1 alleles were more frequently encountered in the group without amyloidosis, whereas the alpha allele was significantly more observed in FMF patients with amyloidosis (p < 0.025). All the MICA alleles were encountered in both patients' groups, but none of them was significantly associated with amyloidosis. CONCLUSIONS: The results suggest a protective effect of the SAA1 beta and gamma alleles on the development of amyloidosis and show the absence of a MICA modifying effect on amyloidosis development. Testing these polymorphisms on a larger sample will lead to more definite conclusions

The Changing Landscape for Stroke\ua0Prevention in AF: Findings From the GLORIA-AF Registry Phase 2

Background GLORIA-AF (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients with Atrial Fibrillation) is a prospective, global registry program describing antithrombotic treatment patterns in patients with newly diagnosed nonvalvular atrial fibrillation at risk of stroke. Phase 2 began when dabigatran, the first non\u2013vitamin K antagonist oral anticoagulant (NOAC), became available. Objectives This study sought to describe phase 2 baseline data and compare these with the pre-NOAC era collected during phase&nbsp;1. Methods During phase 2, 15,641 consenting patients were enrolled (November 2011 to December 2014); 15,092 were eligible. This pre-specified cross-sectional analysis describes eligible patients\u2019 baseline characteristics. Atrial fibrillation&nbsp;disease characteristics, medical outcomes, and concomitant diseases and medications were collected. Data were analyzed using descriptive statistics. Results Of the total patients, 45.5% were female; median age was 71 (interquartile range: 64, 78) years. Patients were from Europe (47.1%), North America (22.5%), Asia (20.3%), Latin America (6.0%), and the Middle East/Africa (4.0%). Most had high stroke risk (CHA2DS2-VASc [Congestive heart failure, Hypertension, Age&nbsp; 6575 years, Diabetes mellitus, previous Stroke, Vascular disease, Age 65 to 74 years, Sex category] score&nbsp; 652; 86.1%); 13.9% had moderate risk (CHA2DS2-VASc&nbsp;= 1). Overall, 79.9% received oral anticoagulants, of whom 47.6% received NOAC and 32.3% vitamin K antagonists (VKA); 12.1% received antiplatelet agents; 7.8% received no antithrombotic treatment. For comparison, the proportion of phase 1 patients (of N&nbsp;= 1,063 all eligible) prescribed VKA was 32.8%, acetylsalicylic acid 41.7%, and no therapy 20.2%. In Europe in phase 2, treatment with NOAC was more common than VKA (52.3% and 37.8%, respectively); 6.0% of patients received antiplatelet treatment; and 3.8% received no antithrombotic treatment. In North America, 52.1%, 26.2%, and 14.0% of patients received NOAC, VKA, and antiplatelet drugs, respectively; 7.5% received no antithrombotic treatment. NOAC use was less common in Asia (27.7%), where 27.5% of patients received VKA, 25.0% antiplatelet drugs, and 19.8% no antithrombotic treatment. Conclusions The baseline data from GLORIA-AF phase 2 demonstrate that in newly diagnosed nonvalvular atrial fibrillation patients, NOAC have been highly adopted into practice, becoming more frequently prescribed than VKA in&nbsp;Europe and North America. Worldwide, however, a large proportion of patients remain undertreated, particularly in&nbsp;Asia&nbsp;and North America. (Global Registry on Long-Term Oral Antithrombotic Treatment in Patients With Atrial Fibrillation [GLORIA-AF]; NCT01468701

Mapping of a New Locus for Autosomal Recessive Demyelinating Charcot-Marie-Tooth Disease to 19q13.1-13.3 in a Large Consanguineous Lebanese Family: Exclusion of MAG as a Candidate Gene

Autosomal recessive Charcot-Marie-Tooth disease (CMT) type 4 (CMT4) is a complex group of demyelinating hereditary motor and sensory neuropathies presenting genetic heterogeneity. Five different subtypes that correspond to six different chromosomal locations have been described. We hereby report a large inbred Lebanese family affected with autosomal recessive CMT4, in whom we have excluded linkage to the already-known loci. The results of a genomewide search demonstrated linkage to a locus on chromosome 19q13.1-13.3, over an 8.5-cM interval between markers D19S220 and D19S412. A maximum pairwise LOD score of 5.37 for marker D19S420, at recombination fraction [θ] .00, and a multipoint LOD score of 10.3 for marker D19S881, at θ=.00, strongly supported linkage to this locus. Clinical features and the results of histopathologic studies confirm that the disease affecting this family constitutes a previously unknown demyelinating autosomal recessive CMT subtype known as “CMT4F.” The myelin-associated glycoprotein (MAG) gene, located on 19q13.1 and specifically expressed in the CNS and the peripheral nervous system, was ruled out as being the gene responsible for this form of CMT

Common and Uncommon Immunoglobulin Haplotypes among Lebanese Communities

Allotypes of IgG1, IgG2, IgG3, and IgA2 subclasses were investigated in seven Lebanese communities (three Moslem and four Christian). The Gm-Am haplotypes found were mainly those prevalent in Caucasians with a low frequency of haplotypes usually observed in Africans and Orientals. The difference between highlanders and lowlanders as expressed by G2m(23) was highly significant and suggested a possible adaptation to selective pressure related to the gamma2 genes, possibly due to endemic malaria in the past. Exceptional Gm-Am haplotypes were unambiguously determined by family studies. Some were characterized either by a deletion or a repression or, in contrast, by a partial or total duplication of gamma genes. Two others had uncommon combinations of allotypes: Gm17;23;5,10,11,13,14 A2m1, where G1m (17) was present without G1m (1); and Gm3;23;5,14 A2m1, where the CH3 allotypes G3m (10,11,13) were lacking

A mutation in OTOF, encoding otoferlin, a FER-1-like protein, causes DFNB9, a nonsyndromic form of deafness

International audienceUsing a candidate gene approach, we identified a novel human gene, OTOF, underlying an autosomal recessive, nonsyndromic prelingual deafness, DFNB9. The same nonsense mutation was detected in four unrelated affected families of Lebanese origin. OTOF is the second member of a mammalian gene family related to Caenorhabditis elegans fer-1. It encodes a predicted cytosolic protein (of 1,230 aa) with three C2 domains and a single carboxy-terminal transmembrane domain. The sequence homologies and predicted structure of otoferlin, the protein encoded by OTOF, suggest its involvement in vesicle membrane fusion. In the inner ear, the expression of the orthologous mouse gene, mainly in the sensory hair cells, indicates that such a role could apply to synaptic vesicles

Evidence for Balancing Selection from Nucleotide Sequence Analyses of Human G6PD

Glucose-6-phosphate dehydrogenase (G6PD) mutations that result in reduced enzyme activity have been implicated in malarial resistance and constitute one of the best examples of selection in the human genome. In the present study, we characterize the nucleotide diversity across a 5.2-kb region of G6PD in a sample of 160 Africans and 56 non-Africans, to determine how selection has shaped patterns of DNA variation at this gene. Our global sample of enzymatically normal B alleles and A, A−, and Med alleles with reduced enzyme activities reveals many previously uncharacterized silent-site polymorphisms. In comparison with the absence of amino acid divergence between human and chimpanzee G6PD sequences, we find that the number of G6PD amino acid polymorphisms in human populations is significantly high. Unlike many other G6PD-activity alleles with reduced activity, we find that the age of the A variant, which is common in Africa, may not be consistent with the recent emergence of severe malaria and therefore may have originally had a historically different adaptive function. Overall, our observations strongly support previous genotype-phenotype association studies that proposed that balancing selection maintains G6PD deficiencies within human populations. The present study demonstrates that nucleotide sequence analyses can reveal signatures of both historical and recent selection in the genome and may elucidate the impact that infectious disease has had during human evolution