Background: Lynch syndrome (LS), the most common inherited form of colorectal cancer (CRC), is responsible for 3% of all cases of CRC. LS is caused by a mismatch repair gene defect and is characterized by a high risk for CRC, endometrial cancer and several other cancers. Identification of LS is of utmost importance because colonoscopic surveillance substantially improves a patient's prognosis.
View Article and Find Full Text PDFArray-based comparative genomic hybridization (aCGH) emerged as a powerful technology for studying copy number variations at higher resolution in many cancers including colorectal cancer. However, the lack of standardized systematic protocols including bioinformatic algorithms to obtain and analyze genomic data resulted in significant variation in the reported copy number aberration (CNA) data. Here, we present genomic aCGH data obtained using highly stringent and functionally relevant statistical algorithms from 116 well-defined microsatellites instable (MSI) and microsatellite stable (MSS) colorectal cancers.
View Article and Find Full Text PDFBackground: Familial breast cancer (BC) represents 5 to 10% of all BC cases. Mutations in two high susceptibility BRCA1 and BRCA2 genes explain 16-40% of familial BC, while other high, moderate and low susceptibility genes explain up to 20% more of BC families. The Lebanese reported prevalence of BRCA1 and BRCA2 deleterious mutations (5.
View Article and Find Full Text PDFNijmegen breakage syndrome is an autosomal recessive disorder caused by biallelic mutation in NBN gene. It is characterized by microcephaly, growth retardation, immuno-deficiency and cancer predisposition. The monoallelic carriers of NBN gene are also reported to be at increased risk of developing various types of malignancy.
View Article and Find Full Text PDFDyskeratosis congenita is a highly pleotropic genetic disorder. This heterogeneity can lead to difficulties in making an accurate diagnosis and delays in appropriate management. The aim of this study was to determine the underlying genetic basis in patients presenting with features of dyskeratosis congenita and who were negative for mutations in the classical dyskeratosis congenita genes.
View Article and Find Full Text PDFColorectal cancer (CRC) is one of the leading causes of cancer mortality. Metastasis remains the primary cause of CRC death. Predicting the possibility of metastatic relapse in early-stage CRC is of paramount importance to target therapy for patients who really need it and spare those with low-potential of metastasis.
View Article and Find Full Text PDFGender-related differences in colorectal cancer (CRC) are not fully understood. Recent studies have shown that CRC arising in females are significantly associated with CpG island methylator phenotype (CIMP-high). Using array comparative genomic hybridization, we analyzed a cohort of 116 CRCs (57 males, 59 females) for chromosomal copy number aberrations (CNA) and found that CRC in females had significantly higher numbers of gains involving chromosome arms 1q21.
View Article and Find Full Text PDFThe Middle East (ME) is an important crossroad where modern humans migrated 'out of Africa' and spread into Europe and Asia. After the initial peopling and long-term isolation leading to well-differentiated populations, the ME also had a crucial role in subsequent human migrations among Africa, Europe and Asia; thus, recent population admixture has been common in the ME. On the other hand, consanguinity, a well-known practice in the ME, often reduces genetic diversity and works in opposition to admixture.
View Article and Find Full Text PDFIn this study, we examined the association between the RKIP expression and the molecular subtypes of breast cancer. Microarray gene expression data of 2,333 human breast cancer from 26 different cohorts performed on Affymetrix U133A or U133Plus2 platforms were downloaded from Array Express and Gene Expression Omnibus and the molecular subtype of breast cancer for the samples was determined by single sample Gene Set Enrichment Analysis. Differences in recurrence-free survival (RFS) were tested using the Log-rank test in univariate analysis and displayed using Kaplan-Meier curves.
View Article and Find Full Text PDFThe Human Variome Project (http://www.humanvariomeproject.org) is an international effort aiming to systematically collect and share information on all human genetic variation.
View Article and Find Full Text PDFDeveloping countries have significantly contributed to the elucidation of the genetic basis of both common and rare disorders, providing an invaluable resource of cases due to large family sizes, consanguinity, and potential founder effects. Moreover, the recognized depth of genomic variation in indigenous African populations, reflecting the ancient origins of humanity on the African continent, and the effect of selection pressures on the genome, will be valuable in understanding the range of both pathological and nonpathological variations. The involvement of these populations in accurately documenting the extant genetic heterogeneity is more than essential.
View Article and Find Full Text PDFThe collection of genetic variants that cause inherited disease (causative mutation) has occurred for decades albeit in an ad hoc way, for research and clinical purposes. More recently, the access to collections of mutations causing specific diseases has become essential for appropriate genetic health care. Because information has accumulated, it has become apparent that there are many gaps in our ability to correctly annotate all the changes that are being identified at ever increasing rates.
View Article and Find Full Text PDFLynch syndrome or hereditary nonpolyposis colorectal cancer (HNPCC) is one of the commonest cancer susceptibility syndromes. It is characterized by early onset colon cancer and a variety of extracolonic tumours. Germline mutations in the DNA mismatch repair genes (MLH1, MSH2, MSH6, PMS1, and PMS2) are responsible for this disorder.
View Article and Find Full Text PDFThe remarkable progress in characterizing the human genome sequence, exemplified by the Human Genome Project and the HapMap Consortium, has led to the perception that knowledge and the tools (e.g., microarrays) are sufficient for many if not most biomedical research efforts.
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