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1.
Forensic Sci Int Genet ; 36: e1-e7, 2018 09.
Artículo en Inglés | MEDLINE | ID: mdl-29909140

RESUMEN

Andean populations have variable degrees of Native American and European ancestry, representing an opportunity to study admixture dynamics in the populations from Latin America (also known as Hispanics). We characterized the genetic structure of two indigenous (Nasa and Pijao) and three admixed (Ibagué, Ortega and Planadas) groups from Tolima, in the Colombian Andes. DNA samples from 348 individuals were genotyped for six mitochondrial DNA (mtDNA), seven non-recombining Y-chromosome (NRY) region and 100 autosomal ancestry informative markers. Nasa and Pijao had a predominant Native American ancestry at the autosomal (92%), maternal (97%) and paternal (70%) level. The admixed groups had a predominant Native American mtDNA ancestry (90%), a substantial frequency of European NRY haplotypes (72%) and similar autosomal contributions from Europeans (51%) and Amerindians (45%). Pijao and nearby Ortega were indistinguishable at the mtDNA and autosomal level, suggesting a genetic continuity between them. Comparisons with multiple Native American populations throughout the Americas revealed that Pijao, had close similarities with Carib-speakers from distant parts of the continent, suggesting an ancient correlation between language and genes. In summary, our study aimed to understand Hispanic patterns of migration, settlement and admixture, supporting an extensive contribution of local Amerindian women to the gene pool of admixed groups and consistent with previous reports of European-male driven admixture in Colombia.


Asunto(s)
Etnicidad/genética , Genética de Población , Indígenas Sudamericanos/genética , Población Blanca/genética , Cromosomas Humanos Y , Colombia/etnología , ADN Mitocondrial/genética , Femenino , Frecuencia de los Genes , Marcadores Genéticos , Variación Genética , Genotipo , Haplotipos , Humanos , Masculino , Reacción en Cadena en Tiempo Real de la Polimerasa
2.
Nat Commun ; 6: 6336, 2015 Mar 19.
Artículo en Inglés | MEDLINE | ID: mdl-25790038

RESUMEN

Papillary renal cell carcinoma (pRCC) is an important subtype of kidney cancer with a problematic pathological classification and highly variable clinical behaviour. Here we sequence the genomes or exomes of 31 pRCCs, and in four tumours, multi-region sequencing is undertaken. We identify BAP1, SETD2, ARID2 and Nrf2 pathway genes (KEAP1, NHE2L2 and CUL3) as probable drivers, together with at least eight other possible drivers. However, only ~10% of tumours harbour detectable pathogenic changes in any one driver gene, and where present, the mutations are often predicted to be present within cancer sub-clones. We specifically detect parallel evolution of multiple SETD2 mutations within different sub-regions of the same tumour. By contrast, large copy number gains of chromosomes 7, 12, 16 and 17 are usually early, monoclonal changes in pRCC evolution. The predominance of large copy number variants as the major drivers for pRCC highlights an unusual mode of tumorigenesis that may challenge precision medicine approaches.


Asunto(s)
Carcinoma de Células Renales/genética , Cromosomas/ultraestructura , Neoplasias Renales/genética , Mutación , Adulto , Anciano , Anciano de 80 o más Años , Anticuerpos Monoclonales/química , Mapeo Cromosómico , Variaciones en el Número de Copia de ADN , Exoma , Exones , Femenino , Regulación Neoplásica de la Expresión Génica , N-Metiltransferasa de Histona-Lisina/genética , Humanos , Pérdida de Heterocigocidad , Masculino , Persona de Mediana Edad , Filogenia , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN
3.
Hum Mol Genet ; 24(5): 1478-92, 2015 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-25378557

RESUMEN

Common variants in the hepatocyte nuclear factor 1 homeobox B (HNF1B) gene are associated with the risk of Type II diabetes and multiple cancers. Evidence to date indicates that cancer risk may be mediated via genetic or epigenetic effects on HNF1B gene expression. We previously found single-nucleotide polymorphisms (SNPs) at the HNF1B locus to be associated with endometrial cancer, and now report extensive fine-mapping and in silico and laboratory analyses of this locus. Analysis of 1184 genotyped and imputed SNPs in 6608 Caucasian cases and 37 925 controls, and 895 Asian cases and 1968 controls, revealed the best signal of association for SNP rs11263763 (P = 8.4 × 10(-14), odds ratio = 0.86, 95% confidence interval = 0.82-0.89), located within HNF1B intron 1. Haplotype analysis and conditional analyses provide no evidence of further independent endometrial cancer risk variants at this locus. SNP rs11263763 genotype was associated with HNF1B mRNA expression but not with HNF1B methylation in endometrial tumor samples from The Cancer Genome Atlas. Genetic analyses prioritized rs11263763 and four other SNPs in high-to-moderate linkage disequilibrium as the most likely causal SNPs. Three of these SNPs map to the extended HNF1B promoter based on chromatin marks extending from the minimal promoter region. Reporter assays demonstrated that this extended region reduces activity in combination with the minimal HNF1B promoter, and that the minor alleles of rs11263763 or rs8064454 are associated with decreased HNF1B promoter activity. Our findings provide evidence for a single signal associated with endometrial cancer risk at the HNF1B locus, and that risk is likely mediated via altered HNF1B gene expression.


Asunto(s)
Mapeo Cromosómico , Neoplasias Endometriales/genética , Sitios Genéticos , Factor Nuclear 1-beta del Hepatocito/genética , Alelos , Estudios de Casos y Controles , Línea Celular Tumoral , Biología Computacional , Bases de Datos Genéticas , Epigénesis Genética , Femenino , Variación Genética , Estudio de Asociación del Genoma Completo , Genotipo , Haplotipos , Factor Nuclear 1-beta del Hepatocito/metabolismo , Humanos , Desequilibrio de Ligamiento , Polimorfismo de Nucleótido Simple , Regiones Promotoras Genéticas , ARN Mensajero/genética , ARN Mensajero/metabolismo , Factores de Riesgo , Población Blanca/genética
4.
Hum Genet ; 134(2): 231-45, 2015 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-25487306

RESUMEN

Several studies have reported associations between multiple cancer types and single-nucleotide polymorphisms (SNPs) on chromosome 5p15, which harbours TERT and CLPTM1L, but no such association has been reported with endometrial cancer. To evaluate the role of genetic variants at the TERT-CLPTM1L region in endometrial cancer risk, we carried out comprehensive fine-mapping analyses of genotyped and imputed SNPs using a custom Illumina iSelect array which includes dense SNP coverage of this region. We examined 396 SNPs (113 genotyped, 283 imputed) in 4,401 endometrial cancer cases and 28,758 controls. Single-SNP and forward/backward logistic regression models suggested evidence for three variants independently associated with endometrial cancer risk (P = 4.9 × 10(-6) to P = 7.7 × 10(-5)). Only one falls into a haplotype previously associated with other cancer types (rs7705526, in TERT intron 1), and this SNP has been shown to alter TERT promoter activity. One of the novel associations (rs13174814) maps to a second region in the TERT promoter and the other (rs62329728) is in the promoter region of CLPTM1L; neither are correlated with previously reported cancer-associated SNPs. Using TCGA RNASeq data, we found significantly increased expression of both TERT and CLPTM1L in endometrial cancer tissue compared with normal tissue (TERT P = 1.5 × 10(-18), CLPTM1L P = 1.5 × 10(-19)). Our study thus reports a novel endometrial cancer risk locus and expands the spectrum of cancer types associated with genetic variation at 5p15, further highlighting the importance of this region for cancer susceptibility.


Asunto(s)
Cromosomas Humanos Par 5/genética , Sitios Genéticos , Proteínas de la Membrana/genética , Modelos Genéticos , Proteínas de Neoplasias/genética , Polimorfismo de Nucleótido Simple , Telomerasa/genética , Cromosomas Humanos Par 5/metabolismo , Bases de Datos de Ácidos Nucleicos , Femenino , Regulación Neoplásica de la Expresión Génica/genética , Haplotipos , Humanos , Proteínas de la Membrana/biosíntesis , Proteínas de Neoplasias/biosíntesis , Regiones Promotoras Genéticas , Factores de Riesgo , Telomerasa/biosíntesis
5.
Gut ; 64(1): 111-20, 2015 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-24647007

RESUMEN

OBJECTIVE: Capecitabine is an oral 5-fluorouracil (5-FU) pro-drug commonly used to treat colorectal carcinoma and other tumours. About 35% of patients experience dose-limiting toxicity. The few proven genetic biomarkers of 5-FU toxicity are rare variants and polymorphisms, respectively, at candidate loci dihydropyrimidine dehydrogenase (DPYD) and thymidylate synthase (TYMS). DESIGN: We investigated 1456 polymorphisms and rare coding variants near 25 candidate 5-FU pathway genes in 968 UK patients from the QUASAR2 clinical trial. RESULTS: We identified the first common DPYD polymorphisms to be consistently associated with capecitabine toxicity, rs12132152 (toxicity allele frequency (TAF)=0.031, OR=3.83, p=4.31×10(-6)) and rs12022243 (TAF=0.196, OR=1.69, p=2.55×10(-5)). rs12132152 was particularly strongly associated with hand-foot syndrome (OR=6.1, p=3.6×10(-8)). The rs12132152 and rs12022243 associations were independent of each other and of previously reported DPYD toxicity variants. Next-generation sequencing additionally identified rare DPYD variant p.Ala551Thr in one patient with severe toxicity. Using functional predictions and published data, we assigned p.Ala551Thr as causal for toxicity. We found that polymorphism rs2612091, which lies within an intron of ENOSF1, was also associated with capecitabine toxicity (TAF=0.532, OR=1.59, p=5.28×10(-6)). ENSOF1 is adjacent to TYMS and there is a poorly characterised regulatory interaction between the two genes/proteins. Unexpectedly, rs2612091 fully explained the previously reported associations between capecitabine toxicity and the supposedly functional TYMS variants, 5'VNTR 2R/3R and 3'UTR 6 bp ins-del. rs2612091 genotypes were, moreover, consistently associated with ENOSF1 mRNA levels, but not with TYMS expression. CONCLUSIONS: DPYD harbours rare and common capecitabine toxicity variants. The toxicity polymorphism in the TYMS region may actually act through ENOSF1.


Asunto(s)
Antimetabolitos Antineoplásicos/efectos adversos , Neoplasias Colorrectales/tratamiento farmacológico , Neoplasias Colorrectales/genética , Desoxicitidina/análogos & derivados , Dihidrouracilo Deshidrogenasa (NADP)/genética , Fluorouracilo/análogos & derivados , Estudios de Asociación Genética , Polimorfismo Genético , Proteínas/genética , Timidilato Sintasa/genética , Adulto , Anciano , Anciano de 80 o más Años , Capecitabina , Desoxicitidina/efectos adversos , Femenino , Fluorouracilo/efectos adversos , Humanos , Hidroliasas , Masculino , Persona de Mediana Edad , Adulto Joven
6.
PLoS One ; 9(1): e85538, 2014.
Artículo en Inglés | MEDLINE | ID: mdl-24465592

RESUMEN

The common -652 6N del variant in the CASP8 promoter (rs3834129) has been described as a putative low-penetrance risk factor for different cancer types. In particular, some studies suggested that the deleted allele (del) was inversely associated with CRC risk while other analyses failed to confirm this. Hence, to better understand the role of this variant in the risk of developing CRC, we performed a multi-centric case-control study. In the study, the variant -652 6N del was genotyped in a total of 6,733 CRC cases and 7,576 controls recruited by six different centers located in Spain, Italy, USA, England, Czech Republic and the Netherlands collaborating to the international consortium COGENT (COlorectal cancer GENeTics). Our analysis indicated that rs3834129 was not associated with CRC risk in the full data set. However, the del allele was under-represented in one set of cases with a family history of CRC (per allele model OR = 0.79, 95% CI = 0.69-0.90) suggesting this allele might be a protective factor versus familial CRC. Since this multi-centric case-control study was performed on a very large sample size, it provided robust clarification of the effect of rs3834129 on the risk of developing CRC in Caucasians.


Asunto(s)
Caspasa 8/genética , Neoplasias Colorrectales/genética , Regiones Promotoras Genéticas , Eliminación de Secuencia , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alelos , Secuencia de Bases , Estudios de Casos y Controles , Neoplasias Colorrectales/etnología , Neoplasias Colorrectales/patología , Femenino , Humanos , Masculino , Persona de Mediana Edad , Datos de Secuencia Molecular , Riesgo , Población Blanca
7.
Hum Mol Genet ; 22(14): 2820-8, 2013 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-23528559

RESUMEN

Accurate duplication of DNA prior to cell division is essential to suppress mutagenesis and tumour development. The high fidelity of eukaryotic DNA replication is due to a combination of accurate incorporation of nucleotides into the nascent DNA strand by DNA polymerases, the recognition and removal of mispaired nucleotides (proofreading) by the exonuclease activity of DNA polymerases δ and ε, and post-replication surveillance and repair of newly synthesized DNA by the mismatch repair (MMR) apparatus. While the contribution of defective MMR to neoplasia is well recognized, evidence that faulty DNA polymerase activity is important in cancer development has been limited. We have recently shown that germline POLE and POLD1 exonuclease domain mutations (EDMs) predispose to colorectal cancer (CRC) and, in the latter case, to endometrial cancer (EC). Somatic POLE mutations also occur in 5-10% of sporadic CRCs and underlie a hypermutator, microsatellite-stable molecular phenotype. We hypothesized that sporadic ECs might also acquire somatic POLE and/or POLD1 mutations. Here, we have found that missense POLE EDMs with good evidence of pathogenic effects are present in 7% of a set of 173 endometrial cancers, although POLD1 EDMs are uncommon. The POLE mutations localized to highly conserved residues and were strongly predicted to affect proofreading. Consistent with this, POLE-mutant tumours were hypermutated, with a high frequency of base substitutions, and an especially large relative excess of G:C>T:A transversions. All POLE EDM tumours were microsatellite stable, suggesting that defects in either DNA proofreading or MMR provide alternative mechanisms to achieve genomic instability and tumourigenesis.


Asunto(s)
ADN Polimerasa III/genética , ADN Polimerasa II/genética , Neoplasias Endometriales/enzimología , Mutación , Adulto , Anciano , Secuencia de Aminoácidos , ADN Polimerasa II/química , ADN Polimerasa II/metabolismo , ADN Polimerasa III/química , ADN Polimerasa III/metabolismo , Neoplasias Endometriales/genética , Femenino , Mutación de Línea Germinal , Humanos , Repeticiones de Microsatélite , Persona de Mediana Edad , Datos de Secuencia Molecular , Proteínas de Unión a Poli-ADP-Ribosa , Estructura Terciaria de Proteína , Alineación de Secuencia , Adulto Joven
8.
Gastroenterology ; 144(1): 53-5, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22999960

RESUMEN

Several single-nucleotide polymorphisms (SNPs) have been associated with colorectal cancer (CRC) susceptibility. Most CRCs arise from adenomas, and SNPs therefore might affect predisposition to CRC by increasing adenoma risk. We found that 8 of 18 known CRC-associated SNPs (rs10936599, rs6983267, rs10795668, rs3802842, rs4444235, rs1957636, rs4939827, and rs961253) were over-represented in CRC-free patients with adenomas, compared with controls. Ten other CRC-associated SNPs (rs6691170, rs6687758, rs16892766, rs7136702, rs11169552, rs4779584, rs9929218, rs10411210, rs4813802, and rs4925386) were not associated significantly with adenoma risk. Genetic susceptibility to CRC in the general population is likely to be mediated in part by predisposition to adenomas.


Asunto(s)
Adenoma/genética , Carcinoma/genética , Neoplasias Colorrectales/genética , Predisposición Genética a la Enfermedad , Alelos , Estudios de Casos y Controles , Femenino , Genotipo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple
9.
Nat Genet ; 45(2): 136-44, 2013 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-23263490

RESUMEN

Many individuals with multiple or large colorectal adenomas or early-onset colorectal cancer (CRC) have no detectable germline mutations in the known cancer predisposition genes. Using whole-genome sequencing, supplemented by linkage and association analysis, we identified specific heterozygous POLE or POLD1 germline variants in several multiple-adenoma and/or CRC cases but in no controls. The variants associated with susceptibility, POLE p.Leu424Val and POLD1 p.Ser478Asn, have high penetrance, and POLD1 mutation was also associated with endometrial cancer predisposition. The mutations map to equivalent sites in the proofreading (exonuclease) domain of DNA polymerases ɛ and δ and are predicted to cause a defect in the correction of mispaired bases inserted during DNA replication. In agreement with this prediction, the tumors from mutation carriers were microsatellite stable but tended to acquire base substitution mutations, as confirmed by yeast functional assays. Further analysis of published data showed that the recently described group of hypermutant, microsatellite-stable CRCs is likely to be caused by somatic POLE mutations affecting the exonuclease domain.


Asunto(s)
Adenoma/genética , Neoplasias Colorrectales/genética , Reparación de la Incompatibilidad de ADN/genética , ADN Polimerasa III/genética , ADN Polimerasa II/genética , Replicación del ADN/genética , Modelos Moleculares , Exodesoxirribonucleasas/genética , Ligamiento Genético , Estudio de Asociación del Genoma Completo , Mutación de Línea Germinal/genética , Humanos , Repeticiones de Microsatélite/genética , Linaje , Proteínas de Unión a Poli-ADP-Ribosa , Schizosaccharomyces/genética , Análisis de Secuencia de ADN
10.
Gut ; 62(1): 83-93, 2013 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-22287596

RESUMEN

OBJECTIVE: Wnt signalling is critical for normal intestinal development and homeostasis. Wnt dysregulation occurs in almost all human and murine intestinal tumours and an optimal but not excessive level of Wnt activation is considered favourable for tumourigenesis. The authors assessed effects of pan-intestinal Wnt activation on tissue homeostasis, taking into account underlying physiological Wnt activity and stem-cell number in each region of the bowel. DESIGN: The authors generated mice that expressed temporally controlled, stabilised ß-catenin along the crypt-villus axis throughout the intestines. Physiological Wnt target gene activity was assessed in different regions of normal mouse and human tissue. Human intestinal tumour mutation spectra were analysed. RESULTS: In the mouse, ß-catenin stabilisation resulted in a graduated neoplastic response, ranging from dysplastic transformation of the entire epithelium in the proximal small bowel to slightly enlarged crypts of non-dysplastic morphology in the colorectum. In contrast, stem and proliferating cell numbers were increased in all intestinal regions. In the normal mouse and human intestines, stem-cell and Wnt gradients were non-identical, but higher in the small bowel than large bowel in both species. There was also variation in the expression of some Wnt modulators. Human tumour analysis confirmed that different APC mutation spectra are selected in different regions of the bowel. CONCLUSIONS: There are variable gradients in stem-cell number, physiological Wnt activity and response to pathologically increased Wnt signalling along the crypt-villus axis and throughout the length of the intestinal tract. The authors propose that this variation influences regional mutation spectra, tumour susceptibility and lesion distribution in mice and humans.


Asunto(s)
Biomarcadores de Tumor/metabolismo , Mucosa Intestinal/metabolismo , Neoplasias Intestinales/metabolismo , Células Madre/fisiología , Vía de Señalización Wnt/fisiología , Animales , Biomarcadores de Tumor/genética , Recuento de Células , Genes APC , Marcadores Genéticos , Homeostasis , Humanos , Hibridación in Situ , Mucosa Intestinal/citología , Mucosa Intestinal/patología , Neoplasias Intestinales/genética , Neoplasias Intestinales/patología , Intestinos/citología , Intestinos/patología , Ratones , Ratones Transgénicos , Mutación , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , beta Catenina/metabolismo
11.
Nat Genet ; 44(10): 1131-6, 2012 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-22961001

RESUMEN

Barrett's esophagus is an increasingly common disease that is strongly associated with reflux of stomach acid and usually a hiatus hernia, and it strongly predisposes to esophageal adenocarcinoma (EAC), a tumor with a very poor prognosis. We report the first genome-wide association study on Barrett's esophagus, comprising 1,852 UK cases and 5,172 UK controls in the discovery stage and 5,986 cases and 12,825 controls in the replication stage. Variants at two loci were associated with disease risk: chromosome 6p21, rs9257809 (Pcombined=4.09×10(-9); odds ratio (OR)=1.21, 95% confidence interval (CI)=1.13-1.28), within the major histocompatibility complex locus, and chromosome 16q24, rs9936833 (Pcombined=2.74×10(-10); OR=1.14, 95% CI=1.10-1.19), for which the closest protein-coding gene is FOXF1, which is implicated in esophageal development and structure. We found evidence that many common variants of small effect contribute to genetic susceptibility to Barrett's esophagus and that SNP alleles predisposing to obesity also increase risk for Barrett's esophagus.


Asunto(s)
Esófago de Barrett/genética , Cromosomas Humanos Par 16 , Predisposición Genética a la Enfermedad , Complejo Mayor de Histocompatibilidad , Polimorfismo de Nucleótido Simple , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Frecuencia de los Genes , Sitios Genéticos , Estudio de Asociación del Genoma Completo , Humanos , Desequilibrio de Ligamiento , Masculino , Persona de Mediana Edad , Modelos Genéticos
12.
Nat Genet ; 44(6): 699-703, 2012 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-22561515

RESUMEN

Hereditary mixed polyposis syndrome (HMPS) is characterized by apparent autosomal dominant inheritance of multiple types of colorectal polyp, with colorectal carcinoma occurring in a high proportion of affected individuals. Here, we use genetic mapping, copy-number analysis, exclusion of mutations by high-throughput sequencing, gene expression analysis and functional assays to show that HMPS is caused by a duplication spanning the 3' end of the SCG5 gene and a region upstream of the GREM1 locus. This unusual mutation is associated with increased allele-specific GREM1 expression. Whereas GREM1 is expressed in intestinal subepithelial myofibroblasts in controls, GREM1 is predominantly expressed in the epithelium of the large bowel in individuals with HMPS. The HMPS duplication contains predicted enhancer elements; some of these interact with the GREM1 promoter and can drive gene expression in vitro. Increased GREM1 expression is predicted to cause reduced bone morphogenetic protein (BMP) pathway activity, a mechanism that also underlies tumorigenesis in juvenile polyposis of the large bowel.


Asunto(s)
Pólipos del Colon/genética , Duplicación de Gen , Péptidos y Proteínas de Señalización Intercelular/genética , Proteínas Morfogenéticas Óseas/antagonistas & inhibidores , Proteínas Morfogenéticas Óseas/genética , Mapeo Cromosómico , Cromosomas Humanos Par 15/genética , Neoplasias Colorrectales/genética , Variaciones en el Número de Copia de ADN , Proteínas Fetales , Forminas , Expresión Génica , Humanos , Péptidos y Proteínas de Señalización Intercelular/metabolismo , Proteínas de Microfilamentos , Proteína 7B2 Secretora Neuroendocrina , Proteínas Nucleares , Receptores Inmunológicos , Familia de Moléculas Señalizadoras de la Activación Linfocitaria , Síndrome
13.
J Med Genet ; 49(3): 158-63, 2012 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-22282540

RESUMEN

Five single nucleotide polymorphisms (SNPs) associated with thyroid cancer (TC) risk have been reported: rs2910164 (5q24); rs6983267 (8q24); rs965513 and rs1867277 (9q22); and rs944289 (14q13). Most of these associations have not been replicated in independent populations and the combined effects of the SNPs on risk have not been examined. This study genotyped the five TC SNPs in 781 patients recruited through the TCUKIN study. Genotype data from 6122 controls were obtained from the CORGI and Wellcome Trust Case-Control Consortium studies. Significant associations were detected between TC and rs965513A (p=6.35×10(-34)), rs1867277A (p=5.90×10(-24)), rs944289T (p=6.95×10(-7)), and rs6983267G (p=0.016). rs6983267 was most strongly associated under a recessive model (P(GG vs GT + TT)=0.004), in contrast to the association of this SNP with other cancer types. However, no evidence was found of an association between rs2910164 and disease under any risk model (p>0.7). The rs1867277 association remained significant (p=0.008) after accounting for genotypes at the nearby rs965513 (p=2.3×10(-13)) and these SNPs did not tag a single high risk haplotype. The four validated TC SNPs accounted for a relatively large proportion (∼11%) of the sibling relative risk of TC, principally owing to the large effect size of rs965513 (OR 1.74).


Asunto(s)
Cromosomas Humanos Par 14/genética , Cromosomas Humanos Par 5/genética , Cromosomas Humanos Par 8/genética , Cromosomas Humanos Par 9/genética , Genes Recesivos , Predisposición Genética a la Enfermedad , Neoplasias de la Tiroides/genética , Estudios de Asociación Genética , Sitios Genéticos , Haplotipos , Humanos , Desequilibrio de Ligamiento , MicroARNs/genética , Polimorfismo de Nucleótido Simple , Análisis de Secuencia de ADN
14.
Hum Mol Genet ; 21(4): 934-46, 2012 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-22076443

RESUMEN

In genome-wide association studies (GWASs) of colorectal cancer, we have identified two genomic regions in which pairs of tagging-single nucleotide polymorphisms (tagSNPs) are associated with disease; these comprise chromosomes 1q41 (rs6691170, rs6687758) and 12q13.13 (rs7163702, rs11169552). We investigated these regions further, aiming to determine whether they contain more than one independent association signal and/or to identify the SNPs most strongly associated with disease. Genotyping of additional sample sets at the original tagSNPs showed that, for both regions, the two tagSNPs were unlikely to identify a single haplotype on which the functional variation lay. Conversely, one of the pair of SNPs did not fully capture the association signal in each region. We therefore undertook more detailed analyses, using imputation, logistic regression, genealogical analysis using the GENECLUSTER program and haplotype analysis. In the 1q41 region, the SNP rs11118883 emerged as a strong candidate based on all these analyses, sufficient to account for the signals at both rs6691170 and rs6687758. rs11118883 lies within a region with strong evidence of transcriptional regulatory activity and has been associated with expression of PDGFRB mRNA. For 12q13.13, a complex situation was found: SNP rs7972465 showed stronger association than either rs11169552 or rs7136702, and GENECLUSTER found no good evidence for a two-SNP model. However, logistic regression and haplotype analyses supported a two-SNP model, in which a signal at the SNP rs706793 was added to that at rs11169552. Post-GWAS fine-mapping studies are challenging, but the use of multiple tools can assist in identifying candidate functional variants in at least some cases.


Asunto(s)
Cromosomas Humanos Par 12/genética , Cromosomas Humanos Par 1/genética , Neoplasias Colorrectales/genética , Predisposición Genética a la Enfermedad/genética , Polimorfismo de Nucleótido Simple/genética , Mapeo Cromosómico , Biología Computacional , Estudio de Asociación del Genoma Completo , Técnicas de Genotipaje , Haplotipos , Humanos , Modelos Logísticos , Programas Informáticos
15.
Carcinogenesis ; 32(12): 1862-6, 2011 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-21965274

RESUMEN

Recent large--scale association studies, both of genome-wide and candidate gene design, have revealed several single-nucleotide polymorphisms (SNPs) which are significantly associated with risk of developing breast cancer. As both breast and endometrial cancers are considered to be hormonally driven and share multiple risk factors, we investigated whether breast cancer risk alleles are also associated with endometrial cancer risk. We genotyped nine breast cancer risk SNPs in up to 4188 endometrial cases and 11,928 controls, from between three and seven Caucasian populations. None of the tested SNPs showed significant evidence of association with risk of endometrial cancer.


Asunto(s)
Neoplasias de la Mama/genética , Neoplasias Endometriales/genética , Predisposición Genética a la Enfermedad , Polimorfismo de Nucleótido Simple , Adolescente , Adulto , Anciano , Estudios de Casos y Controles , Femenino , Humanos , Persona de Mediana Edad , Adulto Joven
16.
J Pathol ; 225(1): 4-11, 2011 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-21630274

RESUMEN

Germline mutations in the FH gene encoding the Krebs cycle enzyme fumarate hydratase predispose to hereditary leiomyomatosis and renal cell cancer (HLRCC) syndrome. FH-deficient cells and tissues accumulate high levels of fumarate, which may act as an oncometabolite and contribute to tumourigenesis. A recently proposed role for fumarate in the covalent modification of cysteine residues to S-(2-succinyl) cysteine (2SC) (termed protein succination) prompted us to assess 2SC levels in our existing models of HLRCC. Herein, using a previously characterized antibody against 2SC, we show that genetic ablation of FH causes high levels of protein succination. We next hypothesized that immunohistochemistry for 2SC would serve as a metabolic biomarker for the in situ detection of FH-deficient tissues. Robust detection of 2SC was observed in Fh1 (murine FH)-deficient renal cysts and in a retrospective series of HLRCC tumours (n = 16) with established FH mutations. Importantly, 2SC was undetectable in normal tissues (n = 200) and tumour types not associated with HLRCC (n = 1342). In a prospective evaluation of cases referred for genetic testing for HLRCC, the presence of 2SC-modified proteins (2SCP) correctly predicted genetic alterations in FH in every case. In two series of unselected type II papillary renal cancer (PRCC), prospectively analysed by 2SCP staining followed by genetic analysis, the biomarker accurately identified previously unsuspected FH mutations (2/33 and 1/36). The investigation of whether metabolites in other tumour types produce protein modification signature(s) that can be assayed using similar strategies will be of interest in future studies of cancer.


Asunto(s)
Carcinoma de Células Renales/diagnóstico , Fumarato Hidratasa/deficiencia , Neoplasias Renales/diagnóstico , Leiomiomatosis/diagnóstico , Síndromes Neoplásicos Hereditarios/diagnóstico , Adulto , Anciano , Animales , Biomarcadores de Tumor/deficiencia , Biomarcadores de Tumor/genética , Biomarcadores de Tumor/metabolismo , Carcinoma de Células Renales/genética , Modelos Animales de Enfermedad , Femenino , Fumarato Hidratasa/genética , Fumarato Hidratasa/metabolismo , Predisposición Genética a la Enfermedad , Mutación de Línea Germinal , Humanos , Neoplasias Renales/genética , Leiomiomatosis/genética , Pérdida de Heterocigocidad , Masculino , Ratones , Ratones Noqueados , Ratones Transgénicos , Persona de Mediana Edad , Síndromes Neoplásicos Hereditarios/genética , Estudios Prospectivos , Sensibilidad y Especificidad , Ácido Succínico/metabolismo
17.
PLoS Genet ; 7(6): e1002105, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21655089

RESUMEN

Genome-wide association studies (GWAS) have identified 14 tagging single nucleotide polymorphisms (tagSNPs) that are associated with the risk of colorectal cancer (CRC), and several of these tagSNPs are near bone morphogenetic protein (BMP) pathway loci. The penalty of multiple testing implicit in GWAS increases the attraction of complementary approaches for disease gene discovery, including candidate gene- or pathway-based analyses. The strongest candidate loci for additional predisposition SNPs are arguably those already known both to have functional relevance and to be involved in disease risk. To investigate this proposition, we searched for novel CRC susceptibility variants close to the BMP pathway genes GREM1 (15q13.3), BMP4 (14q22.2), and BMP2 (20p12.3) using sample sets totalling 24,910 CRC cases and 26,275 controls. We identified new, independent CRC predisposition SNPs close to BMP4 (rs1957636, P = 3.93×10(-10)) and BMP2 (rs4813802, P = 4.65×10(-11)). Near GREM1, we found using fine-mapping that the previously-identified association between tagSNP rs4779584 and CRC actually resulted from two independent signals represented by rs16969681 (P = 5.33×10(-8)) and rs11632715 (P = 2.30×10(-10)). As low-penetrance predisposition variants become harder to identify-owing to small effect sizes and/or low risk allele frequencies-approaches based on informed candidate gene selection may become increasingly attractive. Our data emphasise that genetic fine-mapping studies can deconvolute associations that have arisen owing to independent correlation of a tagSNP with more than one functional SNP, thus explaining some of the apparently missing heritability of common diseases.


Asunto(s)
Proteína Morfogenética Ósea 2/genética , Proteína Morfogenética Ósea 4/genética , Neoplasias Colorrectales/genética , Predisposición Genética a la Enfermedad , Péptidos y Proteínas de Señalización Intercelular/genética , Anciano , Proteína Morfogenética Ósea 2/metabolismo , Proteína Morfogenética Ósea 4/metabolismo , Estudios de Casos y Controles , Neoplasias Colorrectales/metabolismo , Frecuencia de los Genes , Variación Genética , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Persona de Mediana Edad , Polimorfismo de Nucleótido Simple , Carácter Cuantitativo Heredable , Transducción de Señal
18.
Hum Mol Genet ; 20(14): 2879-88, 2011 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-21531788

RESUMEN

We have previously identified several colorectal cancer (CRC)-associated polymorphisms using genome-wide association (GWA) analysis. We sought to fine-map the location of the functional variants for three of these regions at 8q23.3 (EIF3H), 16q22.1 (CDH1/CDH3) and 19q13.11 (RHPN2). We genotyped two case-control sets at high density in the selected regions and used existing data from four other case-control sets, comprising a total of 9328 CRC cases and 10 480 controls. To improve marker density, we imputed genotypes from the 1000 Genomes Project and Hapmap3 data sets. All three regions contained smaller areas in which a cluster of single nucleotide polymorphisms (SNPs) showed clearly stronger association signals than surrounding SNPs, allowing us to assign those areas as the most likely location of the disease-associated functional variant. Further fine-mapping within those areas was generally unhelpful in identifying the functional variation based on strengths of association. However, functional annotation suggested a relatively small number of functional SNPs, including some with potential regulatory function at 8q23.3 and 16q22.1 and a non-synonymous SNP in RPHN2. Interestingly, the expression quantitative trait locus browser showed a number of highly associated SNP alleles correlated with mRNA expression levels not of EIF3H and CDH1 or CDH3, but of UTP23 and ZFP90, respectively. In contrast, none of the top SNPs within these regions was associated with transcript levels at EIF3H, CDH1 or CDH3. Our post-GWA study highlights benefits of fine-mapping of common disease variants in combination with publicly available data sets. In addition, caution should be exercised when assigning functionality to candidate genes in regions discovered through GWA analysis.


Asunto(s)
Mapeo Cromosómico , Cromosomas Humanos Par 16/genética , Cromosomas Humanos Par 19/genética , Cromosomas Humanos Par 8/genética , Neoplasias Colorrectales/genética , Genes Relacionados con las Neoplasias , Polimorfismo de Nucleótido Simple , Estudios de Casos y Controles , Cromosomas Humanos Par 16/metabolismo , Cromosomas Humanos Par 19/metabolismo , Cromosomas Humanos Par 8/metabolismo , Neoplasias Colorrectales/metabolismo , Femenino , Estudio de Asociación del Genoma Completo , Humanos , Masculino
19.
Nat Genet ; 43(5): 451-4, 2011 May.
Artículo en Inglés | MEDLINE | ID: mdl-21499250

RESUMEN

Endometrial cancer is the most common malignancy of the female genital tract in developed countries. To identify genetic variants associated with endometrial cancer risk, we performed a genome-wide association study involving 1,265 individuals with endometrial cancer (cases) from Australia and the UK and 5,190 controls from the Wellcome Trust Case Control Consortium. We compared genotype frequencies in cases and controls for 519,655 SNPs. Forty seven SNPs that showed evidence of association with endometrial cancer in stage 1 were genotyped in 3,957 additional cases and 6,886 controls. We identified an endometrial cancer susceptibility locus close to HNF1B at 17q12 (rs4430796, P = 7.1 × 10(-10)) that is also associated with risk of prostate cancer and is inversely associated with risk of type 2 diabetes.


Asunto(s)
Neoplasias Endometriales/genética , Factor Nuclear 1-beta del Hepatocito/genética , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Estudios de Casos y Controles , Diabetes Mellitus Tipo 2/genética , Femenino , Predisposición Genética a la Enfermedad , Variación Genética , Estudio de Asociación del Genoma Completo , Humanos , Masculino , Persona de Mediana Edad , Oportunidad Relativa , Polimorfismo de Nucleótido Simple , Neoplasias de la Próstata/genética , Factores de Riesgo , Adulto Joven
20.
Nat Genet ; 42(11): 973-7, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20972440

RESUMEN

Genome-wide association studies (GWAS) have identified ten loci harboring common variants that influence risk of developing colorectal cancer (CRC). To enhance the power to identify additional CRC risk loci, we conducted a meta-analysis of three GWAS from the UK which included a total of 3,334 affected individuals (cases) and 4,628 controls followed by multiple validation analyses including a total of 18,095 cases and 20,197 controls. We identified associations at four new CRC risk loci: 1q41 (rs6691170, odds ratio (OR) = 1.06, P = 9.55 × 10⁻¹° and rs6687758, OR = 1.09, P = 2.27 × 10⁻9, 3q26.2 (rs10936599, OR = 0.93, P = 3.39 × 10⁻8), 12q13.13 (rs11169552, OR = 0.92, P = 1.89 × 10⁻¹° and rs7136702, OR = 1.06, P = 4.02 × 10⁻8) and 20q13.33 (rs4925386, OR = 0.93, P = 1.89 × 10⁻¹°). In addition to identifying new CRC risk loci, this analysis provides evidence that additional CRC-associated variants of similar effect size remain to be discovered.


Asunto(s)
Cromosomas Humanos Par 12/genética , Cromosomas Humanos Par 13/genética , Cromosomas Humanos Par 1/genética , Cromosomas Humanos Par 3/genética , Neoplasias Colorrectales/genética , Predisposición Genética a la Enfermedad , Estudio de Asociación del Genoma Completo , Mapeo Cromosómico/métodos , Femenino , Estudio de Asociación del Genoma Completo/métodos , Genotipo , Humanos , Masculino , Metaanálisis como Asunto , Oportunidad Relativa , Análisis de Secuencia por Matrices de Oligonucleótidos , Polimorfismo de Nucleótido Simple , Medición de Riesgo
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