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Objectives: The RANK/RANKL/OPG system is involved in the determination of bone mineral density (BMD) and bone microarchitecture. Our study seeks to evaluate if there are SNPs in the 3'UTR region of the RANK gene associated with osteoporotic phenotypes. Material and methods: Seven genetic variants in 1,098 women from the BARCOS cohort were genotyped, and their association with BMD and osteoporotic fractures evaluated. An interaction with SNP rs9594738 in the RANKL gene which was previously associated with BMD was tested. Results: None of the SNPs were associated significantly with BMD. SNP rs78326403 was associated with wrist/forearm fractures (Log-additive model odds ratio (OR)=3.12 [IC 95%: 1.69 ; 5.75]; p=7.16x10-4), while SNP rs884205 was associated with fractures of the spinal column (OR=4.05 Recessive; [95% CI: 1.59 ; 10.35]; p=8.24x10-3). Lastly, an interaction was detected between SNP rs9594738 from RANKL and rs78326403 from RANK on the presence of fracture (p=0.039). The analysis of the effects of combined genotypes rs9594738 and rs78326403 pointed to an increase in the prevalence of fractures in subjects with a greater number of unfavourable alleles, the ORs being 2.76 [95% CI: 1.30 ; 5.81]; p=0.007) and 5.14 [95% CI: 1.37 ; 15.67]; p=0.007) for 2 and ≥3 unfavourable alleles respectively, in comparison with none/1. Conclusions: Two SNPs in 3'UTR from the RANK gene predispose to site-dependent osteoporotic fracture. An interaction with SNP rs9594738 from RANKL suggests an additive effect of BMD and bone strength. [ABSTRACT FROM AUTHOR]

Background: Tourniquet deflation is associated with profound hemodynamic, respiratory and other organ system derangements. These changes occur with both general and regional anesthesia. Since general and regional anesthesia impact the cardiovascular systems in different ways, we found it worthwhile to evaluate if the magnitude of the systemic effects of tourniquet deflation is differently affected by combined spinal-epidural anesthesia (CSEA) vs. general anesthesia (GA). We hypothesized that during total knee replacement surgery (TKR), CSEA when compared to GA produces less pronounced hemodynamic, respiratory and metabolic changes after tourniquet deflation. Methods: In a parallel group clinical trial, 49 patients undergoing primary (no redo cases included), cemented TKR surgeries were randomly allocated to either CSEA (n=29) or GA (n=20). Mean arterial pressure (MAP) and heart rate (HR) were recorded before anesthesia, 10 min before release of a tourniquet and 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 15 and 30 min after tourniquet release. Arterial pH, standard bicarbonate, base excess, lactate, PaCO2 and PaO2 were measured 10 min before and 10 and 30 min after tourniquet deflation. Results: There was no difference in baseline MAP values. MAP with CSEA was higher vs. GA, 5, 7, 8, 9 and 15 min after tourniquet deflation - 89 mmHg (95% CI 85-93) vs. 82 mmHg (95% CI 78-87) respectively (p < 0.05). At 30 min after tourniquet deflation, the MAP was lower with CSA vs. GA (p <0.05). There was an association between anesthesia type and MAP (F for Test of Between-Subjects Effects = 5.6; df = 1; p < 0.02). At 30 min after tourniquet deflation, HR with CSEA was significant lower compared to GA group. There were no associations between type of anesthesia and pH, standard bicarbonate, base deficit, lactate, PaO2 and PaCO2. Conclusions: Type of anesthesia had a significant, dynamic effect on MAP following tourniquet deflation, but not on the respiratory or metabolic changes. [ABSTRACT FROM AUTHOR]

Niemann-Pick type C (NPC) disease is a childhood autosomal recessive inherited rare neurodegenerative disease characterized by accumulation of cholesterol and glycosphingolipids. Taking into account these mechanisms, we follow a novel approach to deal with NPC disease, by modulating key features of the disease such as inflammation and autophagy, through inhibition of soluble epoxide hydrolase (sEH). Our results suggest that pharmacological inhibition of sEH ameliorate most of the characteristic traits of the NPC in mice, demonstrating that sEH can be considered a potential therapeutic strategy for NPC disease. [Extracted from the article]

Multiple osteochondromatosis (MO), or EXT1/EXT2-CDG, is an autosomal dominant O-linked glycosylation disorder characterized by the formation of multiple cartilage-capped tumors (osteochondromas). In contrast, solitary osteochondroma (SO) is a non-hereditary condition. EXT1 and EXT2, are tumor suppressor genes that encode glycosyltransferases involved in heparan sulfate elongation. We present the clinical and molecular analysis of 33 unrelated Latin American patients (27 MO and 6 SO). Sixty-three percent of all MO cases presented severe phenotype and two malignant transformations to chondrosarcoma (7%). We found the mutant allele in 78% of MO patients. Ten mutations were novel. The disease-causing mutations remained unknown in 22% of the MOpatients and in all SO patients. No second mutational hit was detected in the DNA of the secondary chondrosarcoma from a patient who carried a nonsenseEXT1 mutation. Neither EXT1 nor EXT2 protein could be detected in this sample. This is the first Latin American research program on EXT1/EXT2-CDG. [ABSTRACT FROM AUTHOR]

Niemann-Pick type C ( NPC) disease is a rare autosomal recessive lysosomal storage disease, exhibiting an extremely heterogeneous clinical phenotype. It is a cellular lipid trafficking disorder characterized by the accumulation in the lysosomal/late endosomal system of a variety of lipids, especially unesterified cholesterol. So far two genes, NPC1 or NPC2, have been linked to the disorder. It is a panethnic disease for which two isolates have been described. We present a novel NPC1 mutation (p. A1132P; c. 3394G>C) identified in homozygosity in two patients originating from the same small town of an Aegean Sea island and the results of the broad screening of their extended families. Overall 153 individuals have so far been investigated and a total of 64 carriers were identified. Moreover a common descent of the individuals tested was revealed and all carriers could be traced back to a common surname, apparently originating from a common ancestor couple six generations back. The mutation was found associated with an uncommon haplotype in the island that is also present in other populations. [ABSTRACT FROM AUTHOR]

Canals I, Elalaoui SC, Pineda M, Delgadillo V, Szlago M, Jaouad IC, Sefiani A, Chabás A, Coll MJ, Grinberg D, Vilageliu L. Molecular analysis of Sanfilippo syndrome type C in Spain: seven novel HGSNAT mutations and characterization of the mutant alleles. The Sanfilippo syndrome type C [mucopolysaccharidosis IIIC (MPS IIIC)] is caused by mutations in the HGSNAT gene, encoding an enzyme involved in heparan sulphate degradation. We report the first molecular study on several Spanish Sanfilippo syndrome type C patients. Seven Spanish patients, one Argentinean and three Moroccan patients were analysed. All mutant alleles were identified and comprised nine distinct mutant alleles, seven of which were novel, including four missense mutations (p.A54V, p.L113P, p.G424V and p.L445P) and three splicing mutations due to two point mutations (c.633+1G>A and c.1378-1G>A) and an intronic deletion (c.821-31_821-13del). Furthermore, we found a new single nucleotide polymorphism (SNP) (c.564-98T>C). The two most frequent changes were the previously described c.372-2A>G and c.234+1G>A mutations. All five splicing mutations were experimentally confirmed by studies at the RNA level, and a minigene experiment was carried out in one case for which no fibroblasts were available. Expression assays allowed us to show the pathogenic effect of the four novel missense mutations and to confirm that the already known c.710C>A (p.P237Q) is a non-pathogenic SNP. Haplotype analyses suggested that the two mutations (c.234+1G>A and c.372-2A>G) that were present in more than one patient have a common origin, including one (c.234+1G>A) that was found in Spanish and Moroccan patients. [ABSTRACT FROM AUTHOR]

Macías-Vidal J, Rodríguez-Pascau L, Sánchez-Ollé G, Lluch M, Vilageliu L, Grinberg D, Coll MJ, the Spanish NPC Working Group. Molecular analysis of 30 Niemann-Pick type C patients from Spain. Mutations in the NPC1 or NPC2 gene are responsible for Niemann-Pick type C (NPC) disease (OMIM #257220), an autosomal recessive neurodegenerative lysosomal storage disorder caused by an incorrect regulation of intracellular lipid trafficking. A molecular analysis carried out in 30 unrelated patients identified 43 distinct mutations in the NPC1 gene, 12 of which had not been previously described. The novel NPC1 alleles were four amino acid substitutions (p.F995L, p.F1079S, p.L1106P and p.G1209E), a nonsense mutation (p.E1089X), a 1-bp insertion (p.L1117PfsX4), an in-frame deletion (p.N916del), four intronic changes (c.58-3280C>G, c.882-28A>T, c.2604+5G>A and c.3591+5G>A) that affect the splicing mechanism, and the first deletion including the whole gene described in NPC disease. In all the splice site mutations, the formation of abnormal spliced transcripts was confirmed by cDNA analysis, and mRNA degradation by the nonsense-mediated mRNA decay process was also assessed. As it has been previously reported in this disease, genotype-phenotype correlations are limited due to the large number of private mutations. We describe for the first time one homozygous patient for p.I1061T mutation, who presented the severe infantile clinical onset, and another patient with the variant biochemical phenotype, whose clinical presentation was the neonatal form of the disease. [ABSTRACT FROM AUTHOR]

Urreizti R, Moya-García AA, Pino- Ángeles A, Cozar M, Langkilde A, Fanhoe U, Esteves C, Arribas J, Vilaseca MA, Pérez-Dueñas B, Pineda M, González V, Artuch R, Baldellou, A, Vilarinho L, Fowler B, Ribes A, Sánchez-Jiménez F, Grinberg D, Balcells S. Molecular characterization of five patients with homocystinuria due to severe MTHFR deficiency. Methylenetetrahydrofolate reductase (MTHFR) plays a major role in folate metabolism. Disturbed function of the enzyme results in hyperhomocysteinemia and causes severe vascular and neurological disorders and developmental delay. Five patients suspected of having non-classical homocystinuria due to MTHFR deficiency were examined with respect to their symptoms, MTHFR enzyme activity and genotypes of the MTHFR gene. All patients presented symptoms of severe central nervous system disease. Two patients died, at the ages of 15 months and 14 years. One patient is currently 32 years old, and is being treated with betaine and folinic acid. The other two patients, with an early diagnosis and a severe course of the disease, are currently improving under treatment. MTHFR enzyme activity in the fibroblasts of four of the patients was practically undetectable. We found four novel mutations, three of which were missense changes c.664G> T (p.V218L), c.1316T> C (p.F435S) and c.1733T> G (p.V574G), and the fourth was the 1-bp deletion c.1780delC (p.L590CfsX72). We also found the previously reported nonsense mutation c.1420G> T (p.E470X). All the patients were homozygous. Molecular modelling of the double mutant allele (p.V218L; p.A222V) revealed that affinity for FAD was not affected in this mutant. For the p.E470X mutation, the evidence pointed to nonsense-mediated mRNA decay. In general, genotype-phenotype analysis predicts milder outcomes for patients with missense changes than for those in which mutations led to severe alterations of the MTHFR protein. [ABSTRACT FROM AUTHOR]

Osteoprotegerin plays a key role in bone remodelling. We studied the association between 24 polymorphisms and haplotypes on the OPG gene and bone mineral density and fractures. After multiple-testing correction, one SNP and two block-haplotypes were significantly associated with FN BMD. Two other block-haplotypes were associated with fracture. Osteoprotegerin (OPG) plays a key role in bone remodelling. Here we studied the association between polymorphisms and haplotypes on the OPG gene and bone mineral density (BMD) and fractures. Twenty-four single nucleotide polymorphisms (SNPs) were selected to cover six haplotypic blocks and were genotyped in 964 postmenopausal Spanish women. Haplotypes were established with HaploStats. Association was analysed by GLM (for BMD) and logistic regression (for fractures) both at single SNP and haplotype levels. Upon adjustment for multiple testing ( p < 0.0073), one of the SNPs (SNP #17, rs1032129) remained significantly associated with FN BMD ( p = 0.001). Four block-haplotypes stood multiple-testing correction. Two remained associated with FN BMD and two with fracture. The association of block-4 haplotype “AC” (of SNPs #18 and #17) with FN BMD ( p = 0.0002) was stronger than that of SNP#17 alone and was the best result overall. A global assessment of the results indicated that all the alleles and haplotypes with a protective effect, at p < 0.05, belonged to a frequent long-range haplotype. In conclusion, these results provide a detailed picture of the involvement of common variants and haplotypes of the OPG gene in bone phenotypes. [ABSTRACT FROM AUTHOR]

Genetic studies of osteoporosis have focused on analysing single polymorphisms in individual genes – with inconclusive results. An alternative approach may involve haplotypes and gene-gene interactions. The aim of the study was to test the association between the COL1A1, ESR1, VDR and TGFB1 polymorphisms or haplotypes and bone mineral density (BMD) in Spanish postmenopausal women. Sixteen polymorphisms were analysed in 719 postmenopausal women. ANOVA, ANCOVA and Xi2 tests were used to perform the statistical analysis. COL1A1 -1997G > T ( p = 0.04) and TGFB1 Leu10Pro ( p = 0.02) were found to be associated with adjusted lumbar spine (LS) BMD. Interactions were observed between: the COL1A1 -1997 G/T and Sp1 polymorphisms ( p < 0.01 for LS BMD) and the COL1A1 -1663 indelT and VDR ApaI polymorphisms ( p < 0.01 for femoral neck (FN) BMD). The COL1A1 GDs and ESR1 LPX haplotypes were associated with FN BMD ( p = 0.03 and p = 0.03). Polymorphisms at COL1A1 and TGFB1 and haplotypes at COL1A1 and ESR1 were found to be associated with BMD in a cohort of postmenopausal Spanish women. Moreover, COL1A1 polymorphisms showed significant interactions among them and with the VDR 3′ polymorphisms. [ABSTRACT FROM AUTHOR]