References of "LIBIOULLE, Cécile"
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See detailFemoral-facial syndrome: long term follow-up and associated array CGH abnormalities.
JACQUINET, Adeline ULg; VALDES SOCIN, Hernan Gonzalo ULg; LIBIOULLE, Cécile ULg et al

Poster (2013, October 22)

The femoral-facial syndrome is usually sporadic and its aetiology remains unknown. Non-genetic factors as maternal diabetes mellitus have been associated. Reports of familial cases have otherwise ... [more ▼]

The femoral-facial syndrome is usually sporadic and its aetiology remains unknown. Non-genetic factors as maternal diabetes mellitus have been associated. Reports of familial cases have otherwise suggested autosomal dominant inheritance. We report the 20 years clinical follow-up of a girl with femoral-facial syndrome diagnosed at birth. Recently, array CGH investigation identified a 1400 kb duplication at 9q31.1, including the gene SMC2, and a 343 kb deletion at 12q24.33 including the genes CHFR, ZNF26, ZNF140, ZNF10 and ZNF268. Moreover, the patient presents a Mayer-Rokitansky-Kuster-Hauser syndrome diagnosed at puberty. Femoral-facial syndrome and Mullerian agenesis may reflect different defects in the primary axial mesodermal development, being the consequences of same environmental or/and genetic factors during blastogenesis. Among these genetic factors, we suggest the possible involvement of the two copy number variants reported here [less ▲]

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See detailLes maladies complexes: l'importance de la genetique.
LIBIOULLE, Cécile ULg; BOURS, Vincent ULg

in Revue Médicale de Liège (2012), 67(5-6), 220-5

Complex diseases usually harbour hereditary factors linked with multiple susceptibility genes. The additive effects of genetic and environmental factors are responsible for the pathology. The impact of ... [more ▼]

Complex diseases usually harbour hereditary factors linked with multiple susceptibility genes. The additive effects of genetic and environmental factors are responsible for the pathology. The impact of heredity has been demonstrated through family studies, but also, and mostly, through the study of adopted people and twins. Recently, genome wide association studies (GWAS) allowed the identification of many susceptibility genes for most complex diseases. However, a large part of the heritability is still missing, probably because of insufficient exploration of rare genetic variants and/or epigenetic factors. The ultimate goal of these genetic studies is the definition of an individual risk leading to specific preventive measures (model "predict and prevent"), but this purpose remains very remote for the majority of complex diseases. [less ▲]

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See detailA multi-centre clinico-genetic analysis of the VPS35 gene in Parkinson disease indicates reduced penetrance for disease-associated variants.
Sharma, Manu; Ioannidis, John P. A.; Aasly, Jan O. et al

in Journal of Medical Genetics (2012), 49(11), 721-6

BACKGROUND: Two recent studies identified a mutation (p.Asp620Asn) in the vacuolar protein sorting 35 gene as a cause for an autosomal dominant form of Parkinson disease . Although additional missense ... [more ▼]

BACKGROUND: Two recent studies identified a mutation (p.Asp620Asn) in the vacuolar protein sorting 35 gene as a cause for an autosomal dominant form of Parkinson disease . Although additional missense variants were described, their pathogenic role yet remains inconclusive. METHODS AND RESULTS: We performed the largest multi-center study to ascertain the frequency and pathogenicity of the reported vacuolar protein sorting 35 gene variants in more than 15,000 individuals worldwide. p.Asp620Asn was detected in 5 familial and 2 sporadic PD cases and not in healthy controls, p.Leu774Met in 6 cases and 1 control, p.Gly51Ser in 3 cases and 2 controls. Overall analyses did not reveal any significant increased risk for p.Leu774Met and p.Gly51Ser in our cohort. CONCLUSIONS: Our study apart from identifying the p.Asp620Asn variant in familial cases also identified it in idiopathic Parkinson disease cases, and thus provides genetic evidence for a role of p.Asp620Asn in Parkinson disease in different populations worldwide. [less ▲]

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See detailMeta-analysis identifies 29 additional ulcerative colitis risk loci, increasing the number of confirmed associations to 47.
Anderson, Carl A; Boucher, Gabrielle; Lees, Charlie W et al

in Nature Genetics (2011), 43(3), 246-52

Genome-wide association studies and candidate gene studies in ulcerative colitis have identified 18 susceptibility loci. We conducted a meta-analysis of six ulcerative colitis genome-wide association ... [more ▼]

Genome-wide association studies and candidate gene studies in ulcerative colitis have identified 18 susceptibility loci. We conducted a meta-analysis of six ulcerative colitis genome-wide association study datasets, comprising 6,687 cases and 19,718 controls, and followed up the top association signals in 9,628 cases and 12,917 controls. We identified 29 additional risk loci (P < 5 x 10(-8)), increasing the number of ulcerative colitis-associated loci to 47. After annotating associated regions using GRAIL, expression quantitative trait loci data and correlations with non-synonymous SNPs, we identified many candidate genes that provide potentially important insights into disease pathogenesis, including IL1R2, IL8RA-IL8RB, IL7R, IL12B, DAP, PRDM1, JAK2, IRF5, GNA12 and LSP1. The total number of confirmed inflammatory bowel disease risk loci is now 99, including a minimum of 28 shared association signals between Crohn's disease and ulcerative colitis. [less ▲]

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See detail3-years experience review of neonatal screening for hemoglobin disorders using tandem mass spectrometry.
BOEMER, François ULg; Cornet, Yves ULg; LIBIOULLE, Cécile ULg et al

in Clinica Chimica Acta (2011), 412(15-16), 1476-9

BACKGROUND: Neonatal screening programs for sickle cell disease are common in North America and in some European countries. Isoelectric Focusing or High Performance Liquid Chromatography is the main ... [more ▼]

BACKGROUND: Neonatal screening programs for sickle cell disease are common in North America and in some European countries. Isoelectric Focusing or High Performance Liquid Chromatography is the main technique used for hemoglobin variant detection. METHODS: Since tandem mass spectrometry is being used for screening of inherited metabolic disorders and allows protein identification, we had developed an application to identify the most relevant hemoglobin mutations with this technology. RESULTS: This approach had been previously validated and has been routinely applied in our laboratory for the last three years. We report here our experience with this new method in the field, applied to our East-Belgian population. CONCLUSIONS: To conclude, mass spectrometry provides an efficient alternative approach for laboratories performing neonatal screening of hemoglobin disorders. [less ▲]

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See detailResequencing of positional candidates identifies low frequency IL23R coding variants protecting against inflammatory bowel disease.
Momozawa, Yukihide ULg; Mni, Myriam ULg; Nakamura, Kayo ULg et al

in Nature Genetics (2011), 43(1), 43-7

Genome-wide association studies (GWAS) have identified dozens of risk loci for many complex disorders, including Crohn's disease. However, common disease-associated SNPs explain at most approximately 20 ... [more ▼]

Genome-wide association studies (GWAS) have identified dozens of risk loci for many complex disorders, including Crohn's disease. However, common disease-associated SNPs explain at most approximately 20% of the genetic variance for Crohn's disease. Several factors may account for this unexplained heritability, including rare risk variants not adequately tagged thus far in GWAS. That rare susceptibility variants indeed contribute to variation in multifactorial phenotypes has been demonstrated for colorectal cancer, plasma high-density lipoprotein cholesterol levels, blood pressure, type 1 diabetes, hypertriglyceridemia and, in the case of Crohn's disease, for NOD2 (refs. 14,15). Here we describe the use of high-throughput resequencing of DNA pools to search for rare coding variants influencing susceptibility to Crohn's disease in 63 GWAS-identified positional candidate genes. We identify low frequency coding variants conferring protection against inflammatory bowel disease in IL23R, but we conclude that rare coding variants in positional candidates do not make a large contribution to inherited predisposition to Crohn's disease. [less ▲]

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See detailGenome-wide meta-analysis increases to 71 the number of confirmed Crohn's disease susceptibility loci.
Franke, Andre; McGovern, Dermot P B; Barrett, Jeffrey C et al

in Nature Genetics (2010), 42(12), 1118-25

We undertook a meta-analysis of six Crohn's disease genome-wide association studies (GWAS) comprising 6,333 affected individuals (cases) and 15,056 controls and followed up the top association signals in ... [more ▼]

We undertook a meta-analysis of six Crohn's disease genome-wide association studies (GWAS) comprising 6,333 affected individuals (cases) and 15,056 controls and followed up the top association signals in 15,694 cases, 14,026 controls and 414 parent-offspring trios. We identified 30 new susceptibility loci meeting genome-wide significance (P < 5 x 10). A series of in silico analyses highlighted particular genes within these loci and, together with manual curation, implicated functionally interesting candidate genes including SMAD3, ERAP2, IL10, IL2RA, TYK2, FUT2, DNMT3A, DENND1B, BACH2 and TAGAP. Combined with previously confirmed loci, these results identify 71 distinct loci with genome-wide significant evidence for association with Crohn's disease. [less ▲]

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See detailEvidence for significant overlap between common risk variants for Crohn's disease and ankylosing spondylitis.
Laukens, Debby; Georges, Michel ULg; Libioulle, Cécile ULg et al

in PLoS ONE (2010), 5(11), 13795

BACKGROUND: A multicenter genome-wide association scan for Crohn's Disease (CD) has recently reported 40 CD susceptibility loci, including 29 novel ones (19 significant and 10 putative). To gain insight ... [more ▼]

BACKGROUND: A multicenter genome-wide association scan for Crohn's Disease (CD) has recently reported 40 CD susceptibility loci, including 29 novel ones (19 significant and 10 putative). To gain insight into the genetic overlap between CD and ankylosing spondylitis (AS), these markers were tested for association in AS patients. PRINCIPAL FINDINGS: Two previously established associations, namely with the MHC and IL23R loci, were confirmed. In addition, rs2872507, which maps to a locus associated with asthma and influences the expression of the ORMDL3 gene in lymphoblastoid cells, showed a significant association with AS (p = 0.03). In gut biopsies of AS and CD patients, ORMDL3 expression was not significantly different from controls and no correlation was found with the rs2872507 genotype (Spearman's rho: -0.067). The distribution of p-values for the remaining 36 SNPs was significantly skewed towards low p-values unless the top 5 ranked SNPs (ORMDL3, NKX2-3, PTPN2, ICOSLG and MST1) were excluded from the analysis. CONCLUSIONS: Association analysis using risk variants for CD led to the identification of a new risk variant associated with AS (ORMDL3), underscoring a role for ER stress in AS. In addition, two known and five potentially relevant associations were detected, contributing to common susceptibility of CD and AS. [less ▲]

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See detailGénomique des maladies inflammatoires intestinales
Louis, Edouard ULg; Libioulle, Cécile ULg; Reenaers, Catherine ULg et al

in Revue Médicale de Liège (2009), 64

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See detailCommon variants in the NLRP3 region contribute to Crohn's disease susceptibility.
Villani, Alexandra-Chloé; Lemire, Mathieu; Fortin, Geneviève et al

in Nature Genetics (2009), 41(1), 71-6

We used a candidate gene approach to identify a set of SNPs, located in a predicted regulatory region on chromosome 1q44 downstream of NLRP3 (previously known as CIAS1 and NALP3) that are associated with ... [more ▼]

We used a candidate gene approach to identify a set of SNPs, located in a predicted regulatory region on chromosome 1q44 downstream of NLRP3 (previously known as CIAS1 and NALP3) that are associated with Crohn's disease. The associations were consistently replicated in four sample sets from individuals of European descent. In the combined analysis of all samples (710 father-mother-child trios, 239 cases and 107 controls), these SNPs were strongly associated with risk of Crohn's disease (P(combined) = 3.49 x 10(-9), odds ratio = 1.78, confidence interval = 1.47-2.16 for rs10733113), reaching a level consistent with the stringent significance thresholds imposed by whole-genome association studies. In addition, we observed significant associations between SNPs in the associated regions and NLRP3 expression and IL-1beta production. Mutations in NLRP3 are known to be responsible for three rare autoinflammatory disorders. These results suggest that the NLRP3 region is also implicated in the susceptibility of more common inflammatory diseases such as Crohn's disease. [less ▲]

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See detailGenetic variation in the familial Mediterranean fever gene (MEFV) and risk for Crohn's disease and ulcerative colitis.
Villani, Alexandra-Chloé; Lemire, Mathieu; Louis, Edouard ULg et al

in PLoS ONE (2009), 4(9), 7154

BACKGROUND AND AIMS: The familial Mediterranean fever (FMF) gene (MEFV) encodes pyrin, a major regulator of the inflammasome platform controlling caspase-1 activation and IL-1beta processing. Pyrin has ... [more ▼]

BACKGROUND AND AIMS: The familial Mediterranean fever (FMF) gene (MEFV) encodes pyrin, a major regulator of the inflammasome platform controlling caspase-1 activation and IL-1beta processing. Pyrin has been shown to interact with the gene product of NLRP3, NALP3/cryopyrin, also an important active member of the inflammasome. The NLRP3 region was recently reported to be associated with Crohn's disease (CD) susceptibility. We therefore sought to evaluate MEFV as an inflammatory bowel disease (IBD) susceptibility gene. METHODOLOGY AND RESULTS: MEFV colonic mucosal gene expression was significantly increased in experimental colitis mice models (TNBS p<0.0003; DSS p<0.006), in biopsies from CD (p<0.02) and severe ulcerative colitis (UC) patients (p<0.008). Comprehensive genetic screening of the MEFV region in the Belgian exploratory sample set (440 CD trios, 137 UC trios, 239 CD cases, 96 UC cases, and 107 healthy controls) identified SNPs located in the MEFV 5' haplotype block that were significantly associated with UC (rs224217; p = 0.003; A allele frequency: 56% cases, 45% controls), while no CD associations were observed. Sequencing and subsequent genotyping of variants located in this associated haplotype block identified three synonymous variants (D102D/rs224225, G138G/rs224224, A165A/rs224223) and one non-synonymous variant (R202Q/rs224222) located in MEFV exon 2 that were significantly associated with UC (rs224222: p = 0.0005; A allele frequency: 32% in cases, 23% in controls). No consistent associations were observed in additional Canadian (256 CD trios, 91 UC trios) and Scottish (495 UC, 370 controls) sample sets. We note that rs224222 showed marginal association (p = 0.012; G allele frequency: 82% in cases, 70% in controls) in the Canadian sample, but with a different risk allele. None of the NLRP3 common variants were associated with UC in the Belgian-Canadian UC samples and no significant interactions were observed between NLRP3 and MEFV that could explain the observed flip-flop of the rs224222 risk allele. CONCLUSION: The differences in association levels observed between the sample sets may be a consequence of distinct founder effects or of the relative small sample size of the cohorts evaluated in this study. However, the results suggest that common variants in the MEFV region do not contribute to CD and UC susceptibility. [less ▲]

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See detailCommon variants at five new loci associated with early-onset inflammatory bowel disease.
Imielinski, Marcin; Baldassano, Robert N; Griffiths, Anne et al

in Nature Genetics (2009), 41(12), 1335-40

The inflammatory bowel diseases (IBD) Crohn's disease and ulcerative colitis are common causes of morbidity in children and young adults in the western world. Here we report the results of a genome-wide ... [more ▼]

The inflammatory bowel diseases (IBD) Crohn's disease and ulcerative colitis are common causes of morbidity in children and young adults in the western world. Here we report the results of a genome-wide association study in early-onset IBD involving 3,426 affected individuals and 11,963 genetically matched controls recruited through international collaborations in Europe and North America, thereby extending the results from a previous study of 1,011 individuals with early-onset IBD. We have identified five new regions associated with early-onset IBD susceptibility, including 16p11 near the cytokine gene IL27 (rs8049439, P = 2.41 x 10(-9)), 22q12 (rs2412973, P = 1.55 x 10(-9)), 10q22 (rs1250550, P = 5.63 x 10(-9)), 2q37 (rs4676410, P = 3.64 x 10(-8)) and 19q13.11 (rs10500264, P = 4.26 x 10(-10)). Our scan also detected associations at 23 of 32 loci previously implicated in adult-onset Crohn's disease and at 8 of 17 loci implicated in adult-onset ulcerative colitis, highlighting the close pathogenetic relationship between early- and adult-onset IBD. [less ▲]

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See detailGenetics of ulcerative colitis: the come-back of interleukin 10.
Louis, Edouard ULg; Libioulle, Cécile ULg; Reenaers, Catherine ULg et al

in Gut (2009), 58(9), 1173-6

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See detailGenome-wide association defines more than 30 distinct susceptibility loci for Crohn's disease
Barrett, Jeffrey C.; Hansoul, Sarah ULg; Nicolae, Dan L. et al

in Nature Genetics (2008), 40(8), 955-62

Several risk factors for Crohn's disease have been identified in recent genome-wide association studies. To advance gene discovery further, we combined data from three studies on Crohn's disease (a total ... [more ▼]

Several risk factors for Crohn's disease have been identified in recent genome-wide association studies. To advance gene discovery further, we combined data from three studies on Crohn's disease (a total of 3,230 cases and 4,829 controls) and carried out replication in 3,664 independent cases with a mixture of population-based and family-based controls. The results strongly confirm 11 previously reported loci and provide genome-wide significant evidence for 21 additional loci, including the regions containing STAT3, JAK2, ICOSLG, CDKAL1 and ITLN1. The expanded molecular understanding of the basis of this disease offers promise for informed therapeutic development. [less ▲]

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See detailAn insertion-deletion polymorphism in the Interferon Regulatory Factor 5 (IRF5) gene confers risk of inflammatory bowel diseases
Dideberg, Vinciane ULg; Kristjansdottir, G.; Milani, L. et al

in Human Molecular Genetics (2007), 16(24), 3008-3016

The interferon regulatory factor 5 (IRF5) gene encodes a transcription factor that plays an important role in the innate as well as in the cell-mediated immune responses. The IRF5 gene has been shown to ... [more ▼]

The interferon regulatory factor 5 (IRF5) gene encodes a transcription factor that plays an important role in the innate as well as in the cell-mediated immune responses. The IRF5 gene has been shown to be associated with systemic lupus erythematosus and rheumatoid arthritis. We studied whether the IRF5 gene is also associated with inflammatory bowel diseases (IBD), Crohn disease (CD) and ulcerative colitis (UC). Twelve polymorphisms in the IRF5 gene were genotyped in a cohort of 1007 IBD patients (748 CD and 254 UC) and 241 controls from Wallonia, Belgium. The same polymorphisms were genotyped in a confirmatory cohort of 311 controls and 687 IBD patients (488 CD and 192 UC) from Leuven, Belgium. A strong signal of association [P=1.9x10(-5), odds ratio (OR) 1.81 (1.37-2.39)] with IBD was observed for a 5 bp indel (CGGGG) polymorphism in the promoter region of the IRF5 gene. The association was detectable also in CD patients (P=6.8x10(-4)) and was particularly strong among the UC patients [P=5.3x10(-8), OR=2.42 (1.76-3.34)]. The association of the CGGGG indel was confirmed in the second cohort [P=3.2x10(-5), OR=1.59 (1.28-1.98)]. The insertion of one CGGGG unit is predicted to create an additional binding site for the transcription factor SP1. Using an electrophoretic mobility shift assay, we show allele-specific differences in protein binding to this repetitive DNA-stretch, which suggest a potential function role for the CGGGG indel. [less ▲]

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See detailThe role of the Toll receptor pathway in susceptibility to inflammatory bowel diseases
De Jager, P. L.; Franchimont, D.; Waliszewska, A. et al

in Genes and Immunity (2007), 8(5), 387-397

The intestinal flora has long been thought to play a role either in initiating or in exacerbating the inflammatory bowel diseases (IBD). Host defenses, such as those mediated by the Toll-like receptors ... [more ▼]

The intestinal flora has long been thought to play a role either in initiating or in exacerbating the inflammatory bowel diseases (IBD). Host defenses, such as those mediated by the Toll-like receptors (TLR), are critical to the host/pathogen interaction and have been implicated in IBD pathophysiology. To explore the association of genetic variation in TLR pathways with susceptibility to IBD, we performed a replication study and pooled analyses of the putative IBD risk alleles in NFKB1 and TLR4, and we performed a haplotype-based screen for association to IBD in the TLR genes and a selection of their adaptor and signaling molecules. Our genotyping of 1539 cases of IBD and pooled analysis of 4805 cases of IBD validates the published association of a TLR4 allele with risk of IBD (odds ratio (OR): 1.30, 95% confidence interval (CI): 1.15 - 1.48; P = 0.00017) and Crohn's disease (OR: 1.33, 95% CI: 1.16 - 1.54; P = 0.000035) but not ulcerative colitis. We also describe novel suggestive evidence that TIRAP (OR: 1.16, 95% CI: 1.04 - 1.30; P = 0.007) has a modest effect on risk of IBD. Our analysis, therefore, offers additional evidence that the TLR4 pathway - in this case, TLR4 and its signaling molecule TIRAP - plays a role in susceptibility to IBD. [less ▲]

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See detailNovel Crohn disease locus identified by genome-wide association maps to a gene desert on 5p13.1 and modulates expression of PTGER4.
Libioulle, Cécile ULg; Louis, Edouard ULg; Hansoul, Sarah ULg et al

in PLoS Genetics (2007), 3(4), 538-543

To identify novel susceptibility loci for Crohn disease (CD), we undertook a genome-wide association study with more than 300,000 SNPs characterized in 547 patients and 928 controls. We found three ... [more ▼]

To identify novel susceptibility loci for Crohn disease (CD), we undertook a genome-wide association study with more than 300,000 SNPs characterized in 547 patients and 928 controls. We found three chromosome regions that provided evidence of disease association with p-values between 10(-6) and 10(-9). Two of these (IL23R on Chromosome 1 and CARD15 on Chromosome 16) correspond to genes previously reported to be associated with CD. In addition, a 250-kb region of Chromosome 5p13.1 was found to contain multiple markers with strongly suggestive evidence of disease association (including four markers with p < 10(-7)). We replicated the results for 5p13.1 by studying 1,266 additional CD patients, 559 additional controls, and 428 trios. Significant evidence of association (p < 4 x 10(-4)) was found in case/control comparisons with the replication data, while associated alleles were over-transmitted to affected offspring (p < 0.05), thus confirming that the 5p13.1 locus contributes to CD susceptibility. The CD-associated 250-kb region was saturated with 111 SNP markers. Haplotype analysis supports a complex locus architecture with multiple variants contributing to disease susceptibility. The novel 5p13.1 CD locus is contained within a 1.25-Mb gene desert. We present evidence that disease-associated alleles correlate with quantitative expression levels of the prostaglandin receptor EP4, PTGER4, the gene that resides closest to the associated region. Our results identify a major new susceptibility locus for CD, and suggest that genetic variants associated with disease risk at this locus could modulate cis-acting regulatory elements of PTGER4. [less ▲]

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See detailChanges in major intracellular osmolytes in L-929 cells following rapid and slow application of hyperosmotic media.
Libioulle, Cécile ULg; Corbesier, L.; Gilles, Raymond ULg

in Comparative Biochemistry & Physiology Part A : Molecular & Integrative Physiology (2001), 130(3), 461-70

Cultured L-929 cells respond to media-made hyperosmotic (600 mOsmol/kg H2O) by addition of NaCl, sorbitol or proline by adjusting successively their intracellular level in different osmolytes: Na+, K ... [more ▼]

Cultured L-929 cells respond to media-made hyperosmotic (600 mOsmol/kg H2O) by addition of NaCl, sorbitol or proline by adjusting successively their intracellular level in different osmolytes: Na+, K+, amino acids and sorbitol. In the NaCl medium, Na+ and K+ are first to increase. Their concentration is then down-regulated while they are replaced by less disrupting osmolytes: amino acids and sorbitol. The amino-acid level is also adjusted with respect to the increase in sorbitol which starts only after 24 h, depending on the induction of aldose reductase. A similar evolution in the amount of these osmolytes is observed, with different time scales and amplitudes, depending on whether the osmotic shocks are applied abruptly or slowly, in a more physiological way. The interplay between the osmolytes is also different depending on their availability in the external medium. Such complex evolutions indicate that a cascade of interacting signals must be considered to account for the overall regulation process. It can hardly be fitted into a model implicating a single primary signalling event (early increase in ions or decrease in cell volume) as usually postulated. Also, the volume up-regulation is not significantly different in the different conditions, showing that it is not primarily dependent on the adjustment of the intracellular osmolarity which is reached immediately upon cell shrinkage and is maintained all over, independently of the availability and changes in nature of the osmolytes. [less ▲]

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