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At least 469 records · Page 26Linked to original sources
PubMed2006

Association of V227A PPARalpha polymorphism with altered serum biochemistry and alcohol drinking in Japanese men.

OBJECTIVES: Peroxisome proliferator-activated receptor (PPAR) alpha plays a major role in alcoholic liver disease in rodents. The two-fold objective of our study was to determine the presence of PPARalpha polymorphisms and their frequencies in Japanese populations and then to evaluate the effects of any alleles on metabolic parameters and alcohol drinking. METHODS: Analysis of coding SNP in PPARalpha was performed in 706 Japanese men; from these subjects 655 men were further studied after exclusion criteria were applied. RESULTS: PPARalpha-V227A, which has not been reported in Europe and North America as a major polymorphism, was discovered with the frequency of 0.05. PPARalpha-L162V was found in European and North American populations, but not in Japanese, thus confirming the ethnic differences in PPARalpha allele frequencies. The A227 allele was associated with increased serum concentrations of gamma glutamyltranspeptidase. In non-drinkers, the total cholesterol (TC) levels were significantly lower in those having the PPARalpha-V227A polymorphism. In drinkers, however, it was comparable among V227A polymorphisms, and conversely higher in those having both A227 and aldehyde dehydrogenase 2 (ALDH2) variants when further divided according to the ALDH2 polymorphism. Significant interactions between PPARalpha-V227A polymorphism and drinking were also found for TC, triglyceride levels and AST/ALT ratios. These results suggest that the activity of the A227 allele without drinking may be higher than in wild-type allele, but its activity may become lower during drinking habits. CONCLUSION: PPARalpha-V227A is a major polymorphism in the Japanese population, and its activity may be greater compared to wild-type, but decreased by alcohol drinking.

Alcohol Drinking↗
PubMed2026

Prevalence and Genomic Characterization of mcr-Positive Enterobacteriaceae in Retail Meat in Thailand Following the Colistin Ban.

This study aimed to investigate the prevalence and characteristics of mcr-positive Enterobacteriaceae in retail meat in Thailand following the national ban on prophylactic colistin use in food producing animals. A total of 152 meat samples (103 chicken and 49 pork) were collected from supermarkets and open markets between July and September 2023. Samples were screened for mcr-1 to mcr-5 using multiplex PCR. None of the samples from supermarkets tested positive, whereas mcr genes were detected in 15.4% (6/39) and 13.3% (4/30) of chicken and pork samples, respectively, from open markets, with mcr-1 and/or mcr-3 identified. A total of 21 isolates were recovered from PCR-positive samples (11 from chicken and 10 from pork). Escherichia coli was the predominant species (n = 19), followed by Klebsiella pneumoniae (n = 2). All mcr-positive isolates exhibited multidrug resistance. Whole-genome sequencing was performed for 19 non-clonal isolates. One K. pneumoniae strain from a pork sample co-harbored mcr-1 and mcr-8, representing the first report of this combination in the animal sector in Thailand. In addition, virulence-associated genes, including adhesion factors, toxins, and iron acquisition systems, were identified in selected isolates. Core genome SNP-based phylogenetic analysis revealed substantial genomic diversity among the isolates, suggesting relatedness to strains reported prior to the colistin ban. These findings indicate that retail meat from open markets may serve as an important route for the transmission of mcr-positive bacteria in Thailand and highlight the urgent need to incorporate systematic retail meat surveillance into national antimicrobial resistance monitoring programs.

Animals↗
PubMed2006

Association study between kynurenine 3-monooxygenase gene and schizophrenia in the Japanese population.

Several lines of evidence suggest that metabolic changes in the kynurenic acid (KYNA) pathway are related to the etiology of schizophrenia. The inhibitor of kynurenine 3-monooxygenase (KMO) is known to increase KYNA levels, and the KMO gene is located in the chromosome region associated with schizophrenia, 1q42-q44. Single-marker and haplotype analyses for 6-tag single nucleotide polymorphisms (SNPs) of KMO were performed (cases = 465, controls = 440). Significant association of rs2275163 with schizophrenia was observed by single-marker comparisons (P = 0.032) and haplotype analysis including this SNP (P = 0.0049). Significant association of rs2275163 and haplotype was not replicated using a second, independent set of samples (cases = 480, controls = 448) (P = 0.706 and P = 0.689, respectively). These results suggest that the KMO is unlikely to be related to the development of schizophrenia in Japanese.

Aged↗
PubMed2004

HSD17B1 gene polymorphisms and risk of endometrial and breast cancer.

Estrogen exposure influences breast and endometrial cancer risk. The HSD17B1 gene produces an enzyme that catalyzes the conversion of estrone to estradiol. We hypothesized that genetic variations in HSD17B1 gene may alter endogenous estrogen levels and, thus, influence endometrial and breast cancer risk. We validated and genotyped polymorphisms in the HSD17B1 gene and assessed whether these single nucleotide polymorphisms (SNPs), or the imputed haplotypes, were associated with endometrial and breast cancer risk. We also assessed whether a priori risk factors modified the associations between HSD17B1 genotype and cancer risk, and whether HSD17B1 genotypes were associated with plasma estrogen levels among postmenopausal women not using hormone replacement therapy. Ten SNPs of HSD17B1 gene were validated in 30 women from the Nurses' Health Study. Using the expectation maximization algorithm, three common (>5% frequency) haplotypes accounted for 97% of the chromosomes at this locus, and seven SNPs were in complete linkage disequilibrium. We identified and genotyped two haplotype-tagging SNPs (+1004C/T and +1322C/A), and genotyped an additional SNP [+1954A/G (Ser312Gly)] in nested case-control studies of endometrial cancer (cases = 222, controls = 666) and breast cancer (cases = 1007, controls = 1441) in the prospective Nurses' Health Study. Although no overall association by SNP or haplotype analysis was observed with endometrial or breast cancer risk, the +1954A/A genotype was associated with higher estradiol levels in lean women (P = 0.01) and interaction between the +1954 genotype with body mass index in postmenopausal breast cancer (P = 0.05) was suggested. These findings suggest that the HSD17B1 may be associated with circulating estradiol levels and interact with body mass index in postmenopausal breast cancer.

Adult↗
PubMed2006

Variation of the N-acetyltransferase 2 gene in a Romanian and a Kyrgyz population.

As part of a project on environmental disasters in minority populations, this study aimed to evaluate differences in the sequence of N-acetyltransferase 2 (NAT2) as a metabolic susceptibility gene in yet unexplored ethnicities. Eight single nucleotide polymorphisms (SNP) in the NAT2 coding region and a variant in the 3' flanking region were analyzed in 290 unrelated Kyrgyz and 140 unrelated Romanians by SNP-specific PCR analysis. The variants 341C, 481T, and 803G were less and 857A more prevalent in Kyrgyz (P < 0.0001). The variant at site 857 indicates Asian descent. 282C>T and 590G>A showed no significant variation by ethnicity. 364G>A and 411A>T turned out to be monomorphic. Database comparisons of the NAT2 minor allele frequencies support that Romanians belong to Caucasians and Kyrgyz are in between Caucasians and East Asians. The distributions of predicted haplotypes differed significantly between the two ethnicities where the Kyrgyz showed a higher genetic diversity. The haplotype without mutations was more common in Kyrgyz (40.1% in Kyrgyz, 29.3% in Romanians). Accordingly, the imputed slow acetylator phenotype was less prevalent in Kyrgyz (35.2% versus 51.4% in Romanians). We found pronounced ethnic differences in NAT2 genotypes with yet unknown effect on the health risks for environmental or occupational exposures in minority populations.

Acetylation↗
PubMed2005

Genome-wide linkage analyses and candidate gene fine mapping for HDL3 cholesterol: the Framingham Study.

High density lipoprotein cholesterol (HDL-C) is inversely associated with coronary heart disease and has a genetic component; however, linkage to HDL-C is not conclusive. Subfractions of HDL, such as HDL(3)-C, may be better phenotypes for linkage studies. Using HDL(3)-C levels measured on 907 Framingham Heart Study subjects from 330 families around 1987, we conducted a genome-wide variance components linkage analysis with 401 microsatellite markers spaced approximately 10 centimorgan (cM) apart. Nine candidate genes were identified and annotated using a bioinformatics approach in the region of the highest linkage peak. Twenty-eight single nucleotide polymorphisms (SNPs) were selected from these candidate genes, and linkage and family-based association fine mapping were conducted using these SNPs. The highest multipoint log-of-the-odds (LOD) score from the initial linkage analysis was 3.7 at 133 cM on chromosome 6. Linkage analyses with additional SNPs yielded the highest LOD score of 4.0 at 129 cM on chromosome 6. Family-based association analysis revealed that SNP rs2257104 in PLAGL1 at approximately 143 cM was associated with multivariable adjusted HDL(3) (P = 0.03). Further study of the linkage region and exploration of other variants in PLAGL1 are warranted to define the potential functional variants of HDL-C metabolism.

Adult↗
PubMed2006

Association of PTPN22 haplotypes with Graves' disease.

CONTEXT: A recent study reported associations of a series of single nucleotide polymorphisms (SNPs) within PTPN22, including rs2476601, with rheumatoid arthritis. OBJECTIVE: Having previously reported significant association of the T allele of rs2476601 in a Graves' disease (GD) cohort, we sought to determine whether novel rheumatoid arthritis-associated SNPs were also contributing to susceptibility to GD. DESIGN: Case control and family-based studies of five PTPN22 tag SNPs were performed. SETTING: An United Kingdom academic department of medicine was the setting for the study. PATIENTS OR OTHER PARTICIPANTS: A total of 768 GD patients, 768 control subjects, and 313 families with autoimmune thyroid disease participated. MAIN OUTCOME MEASURE: Tests for association with disease were the main outcome measure. RESULTS: No association with disease of any of the individual SNPs and no correlation between genotype and clinical phenotype were seen. However, haplotype analysis of the SNP markers with addition of rs2476601 did reveal a strong association of a haplotype containing the T allele, in both the case control (chi2 = 29.13; P = 6.77 x 10(-8)) and family data sets (chi2 = 5.24; P = 0.02). Furthermore, a novel protective effect of a haplotype containing all six SNPs was observed (chi2 = 17.02; P = 3.7 x 10(-5)). CONCLUSIONS: These data suggest that the association of SNPs within the PTPN22 region differs between autoimmune diseases, occurring individually and/or as part of a haplotype, indicating that the mechanisms by which PTPN22 confers susceptibility to GD may, in part, be disease specific.

Arthritis, Rheumatoid↗
PubMed1997

Nitric oxide inhibits corticotropin-releasing hormone exocytosis but not synthesis by cultured human trophoblasts.

Nitric oxide (NO) plays an important role in many cell-cell signaling systems, but its mechanism of action is variable. We have previously reported that NO reduces secretion of the peptide hormone, CRH, from cultured placental cells and the perfused placenta. Because placental CRH production seems linked to human parturition, we wished to explore the mechanism of action of NO in this setting in more detail. We report here that in the placenta, NO specifically inhibited CRH exocytosis, not synthesis, and that endogenous NO affects this process. Cytotrophoblasts were prepared from term human placentas and cultured as monolayers. CRH immunoreactivity in the cell supernatants and cell extracts were measured by RIA. CRH messenger RNA was determined by Northern blot analysis. Sodium nitroprusside (SNP; 1-100 mumol/L) and S-nitroso-N-acetyl-penicillamine (SNAP; 1-100 mumol/L), NO donors, significantly reduced basal CRH concentration in the media, while increasing the concentration of CRH in the cells (P < 0.01), suggesting that exocytosis of CRH was inhibited. These effects could be attenuated by the NO scavenger hemoglobin (20 micrograms/mL). KCl (45 mmol/L), which causes exocytosis by depolarizing the cell membrane, increased CRH release by 2- to 3-fold, and this was inhibited by SNP. Basal release of CRH was augmented by the NO synthase competitive inhibitor N omega-L-arginine methyl ester (1 mmol/L; P < 0.01) and the guanylate cyclase inhibitor, LY83583 (1 mumol/L; P < 0.01). The inhibitory effect of SNP was also blocked by LY83583. CRH messenger RNA content did not change when the placental cells were incubated with SNP, N omega-L-arginine methyl ester, and LY83583 for 6 and 24 h, and this was consistent with studies showing that total CRH immunoreactivity (cells plus media) did not change in the presence of SNP. These studies indicate that exogenous NO inhibits CRH exocytosis, rather than biosynthesis, by human trophoblasts and that endogenous NO has tonic inhibitory effects on CRH release by these cells. The inhibitory effect of NO on basal and stimulated CRH release by placental trophoblasts seems to be a guanylate cyclase-mediated inhibition of exocytosis.

Adult↗
PubMed2001

Vitamin D receptor gene polymorphisms are associated with obesity in type 2 diabetic subjects with early age of onset.

OBJECTIVE: Allelic variations in the vitamin D receptor (VDR) gene were reported to modulate insulin secretion in response to glucose. VDR was investigated as a candidate gene for type 2 diabetes mellitus (T2DM). METHOD: Four single nucleotide polymorphisms (SNPs) in intron 8 (BsmI, Tru9I, ApaI) and exon 9 (TaqI) of the VDR gene were examined in 309 unrelated French subjects with T2DM and 143 controls. RESULTS: The distribution of alleles and genotypes of the four SNPs was similar in patients and controls. However, in patients whose age at diagnosis of diabetes was < or =45 years, homozygous subjects for the T-allele of the TaqI SNP had a higher body mass index (BMI) (31.7+/-6.7 kg/m2, P=0.0058) and an increased prevalence of obesity (81%, P=0.005) with respect to heterozygous subjects (27.9+/-5.0 kg/m2; 46%) or homozygous subjects for the t-allele (27.7+/-5.0 kg/m2; 52%). Similar results were observed for homozygous subjects for the b-allele of the BsmI SNP. Logistic regression analysis demonstrated that TT homozygosity was independently associated with obesity in these subjects (odds ratio, 4.64; 95% confidence interval (CI), 1.64-14.76; P=0.0056). CONCLUSION: VDR is not a major gene for T2DM in French Caucasians. However, polymorphisms in the VDR gene are associated with the susceptibility to obesity in subjects with early-onset T2DM. The pathophysiological mechanisms of these associations remain unexplained, but they could be related to a direct effect of vitamin D in adypocyte differentiation and metabolism, or to an indirect effect by modulation of insulin secretion.

Age of Onset↗
PubMed2004

[Single nucleotide polymorphism and its application in allogeneic hematopoietic stem cell transplantation--review].

Single nucleotide polymorphism (SNP) is the third genetic marker after restriction fragment length polymorphism (RFLP) and short tandem repeat. It represents the most density genetic variability in the human genome and has been widely used in gene location, cloning, and research of heredity variation, as well as parenthood identification in forensic medicine. As steady heredity polymorphism, single nucleotide polymorphism is becoming the focus of attention in monitoring chimerism and minimal residual disease in the patients after allogeneic hematopoietic stem cell transplantation. The article reviews SNP heredity characterization, analysis techniques and its applications in allogeneic stem cell transplantation and other fields.

Hematopoietic Stem Cell Transplantation↗
PubMed2004

ADAM33 polymorphisms and phenotype associations in childhood asthma.

BACKGROUND: A disintegrin and metalloproteinase (ADAM) 33 has been implicated as an asthma susceptibility gene by using a positional cloning approach. However, genetic linkage of asthma phenotypes to chromosome 20p13 (the location of ADAM33) has not been observed in most asthma genome scans, and it is unclear whether these associations with ADAM33 are broadly generalizable. OBJECTIVE: To examine whether ADAM33 is associated with asthma in a North American population of childhood asthmatic patients. METHODS: We performed a family-based association study by using 652 nuclear families ascertained through asthmatic subjects enrolled in a large randomized clinical trial. Seventeen ADAM33 single nucleotide polymorphisms (SNPs; including 9 associated with asthma in the initial report) were genotyped by mass spectrometry. Single-SNP and haplotype association analysis was performed. RESULTS: Among white and African American subjects, no single-SNP association with asthma was observed. However, a common 16-SNP haplotype (frequency, 14.6% in white subjects) was associated with asthma (P=.006). Two SNPs in strong linkage disequilibrium (T1 and T+1) were marginally associated with asthma in the Hispanic cohort (P=.04). These data provide marginal support for an asthma locus in the ADAM33 genomic region. However, the magnitudes of the observed associations are modest at best and are inconsistent with the original report. CONCLUSIONS: We conclude that either ADAM33 has only modest effects on asthma susceptibility, and the initial reports of association were a result of analysis in a selected population, or the initial findings were a result of chance. It is also possible that the true asthma susceptibility locus in this genomic region is near, but not at, ADAM33.

ADAM Proteins↗
PubMed2003

Microchip electrophoresis of tagged probes incorporated with one-colored ddNTP for analyzing single-nucleotide polymorphisms.

We demonstrate a simple and rapid method for SNP typing, allele frequency determination, and trace mutant analysis that works with even an inexpensive detection system. This method is based on microchip electrophoresis of tagged probes incorporated with one-colored ddNTP (METPOC). The assay uses dye terminator incorporation into a pair of probes of different lengths specific to wild- and mutant-type targets, respectively. They are hybridized to the targets prior to ddNTP-Cy-5 incorporation, which occurs only for a matched probe-target duplex. Because the extension reactions for the two probes are carried out simultaneously in one tube and the products from both probes are analyzed in one channel by one-color fluorescence detection, an accurate comparative analysis of SNPs is possible. SNP typing as well as allele frequency determination in the range above 0.1% can easily be carried out using a commercial microchip electrophoresis system in a few minutes.

Alleles↗
PubMed2007

A haplotype-linkage analysis method for estimating recombination rates using dense SNP trio data.

Meiotic recombination is an important evolution force in shaping human genomes and creating human diversity. Recent explorations suggest that meiotic recombination events tend to happen in certain regions of the genome, leading to the hypothesis of recombination hot spots. To identify such hot spots, we describe an empirical method for estimating the recombination rate, which reflects both historical and current meiotic events, using unphased genotypes from nuclear families, in particular, parents-child trios. The key idea is that use of the haplotypic polymorphisms with multiple adjacent SNPs will increase the number of informative meioses and hence would improve the power of linkage analysis. Since haplotypes of individuals are not directly observed, e.g., in HapMap data, we infer the haplotypes simultaneously while estimating recombination rate. We refer this described method as haplotype-linkage (HALIN) method. Our simulation results show that HALIN gives unbiased estimates of recombination rate. We apply HALIN to analyze the genotype data of chromosome 20 from HapMap data and compare the results to the results using two existing methods, Bayesian coalescent method described by McVean et al. [2004] science 304:581-584 and empirical method by Clarke and Cardon ([2005] Genetics). Results suggest that HALIN identified 75 hot spots on chromosome 20, and 85% of them are also identified by the method by McVean et al. ([2004] science 304:581-584), in addition to a few new hot spots. In comparison with Clarke and Cardon's result, estimated recombination rates (RRs) under these 75 hot spots are significantly greater than those outside of hot spots, which support the general consistency in discovering recombination hot spots between two methods.

Child↗
PubMed2005

Survey of a cDNA library from the turkey (Meleagris gallopavo).

Genome characterization and analysis is an imperative step in identifying and selectively breeding for improved traits of agriculturally important species. Expressed sequence tags (ESTs) represent a transcribed portion of the genome and are an effective way to identify genes within a species. Downstream applications of EST projects include DNA microarray construction and interspecies comparisons. In this study, 694 ESTs were sequenced and analyzed from a library derived from a 24-day-old turkey embryo. The 437 unique sequences identified were divided into 76 assembled contigs and 361 singletons. The majority of significant comparative matches occurred between the turkey sequences and sequences reported from the chicken. Whole genome sequence from the chicken was used to identify potential exon-intron boundaries for selected turkey clones and intron-amplifying primers were developed for sequence analysis and single nucleotide polymorphism (SNP) discovery. Identified SNPs were genotyped for linkage analysis on two turkey reference populations. This study significantly increases the number of EST sequences available for the turkey.

Animals↗
PubMed2003

Designing an optimum genetic association study using dense SNP markers and family-based sample.

Genetic association analysis using thousands of single nucleotide polymorphism (SNP) markers has become a promising alternative to genome-wide linkage scan. Analysis based on linkage-disequilibrium (LD) is more efficient because meiotic information of past generations is utilized. However, in addition to the physical distance between the disease locus and a marker locus, numerous other factors such as admixture, genetic drift, and multiple mutations can affect the observed value of LD. The effect of these factors in a genomic LD association study must be carefully analyzed to obtain an efficient study design. In the following review, we consider studies using family-based data and carefully study the effects of some of these important design factors, including the sample size, frequency of SNP markers, and marker density. For example, we conclude that (1) for reasonably frequent SNP markers, a moderately large sample of 500 families is appropriate for a moderately stringent significance level (alpha = 0.00009); (2) to maintain a power of 80%, maximal difference in allele frequencies between the disease gene and a SNP marker varies between 0.1 (under additive model) and 0.5 (multiplicative); (3) a map density of 10 cM is appropriate only under idea scenario (moderately large sample size, equal trait/marker allele frequencies, maximum LD strength etc.). Results shown here should have practical implications to designing efficient LD association studies using dense SNP markers.

Epidemiologic Research Design↗
PubMed2004

Chicken single nucleotide polymorphism identification and selection for genetic mapping.

Single nucleotide polymorphisms (SNP) are the ideal markers for high-density genome wide mapping. A total of 327,000 expressed sequence tag (EST) sequences, obtained from the ChickEST project, were examined for the presence of SNP. A total of 32,268 potential chicken SNP were identified and stored in a customized Microsoft Access database and evaluated in silico for their usability for a high-density genetic map. Based on a minimum of 3 for the minor allele occurrence and a minimum of 30% for the minor allele frequency, 5,332 reliable SNP were selected, of which both SNP alleles were present in the database at a high frequency. To test the usefulness of the in silico SNP identification, 24 SNP affecting a BglII site were used for a genotyping study. A functional PCR assay could be designed for 21 of the 24 SNP. It was possible to validate 90% of this marker subset (21 SNP) by BglII restriction analysis. The high percentage of validated markers demonstrates the reliability of the 5,332 chicken SNP markers. Furthermore, the limited number of genomic DNA samples necessary to validate 90% of the SNP markers confirmed the prediction of the high frequency at which both alleles of the selected SNP were present in the tested chicken populations.

Animals↗
PubMed2000

The induction of cell death in human osteoarthritis chondrocytes by nitric oxide is related to the production of prostaglandin E2 via the induction of cyclooxygenase-2.

There is increasing evidence suggesting that chondrocyte death may contribute to the progression of osteoarthritis (OA). This study focused on the characterization of signaling cascade during NO-induced cell death in human OA chondrocytes. The NO generator, sodium nitroprusside (SNP), promoted chondrocyte death in association with DNA fragmentation, caspase-3 activation, and down-regulation of Bcl-2. Both caspase-3 inhibitor Z-Asp(OCH3)-Glu(OCH3)-Val-Asp(OCH3)-CH2F and caspase-9 inhibitor Z-Leu-Glu(OCH3)-His-Asp(OCH3)-CH2F prevented the chondrocyte death. Blocking the mitogen-activated protein kinase pathway by the mitogen-activated protein kinase kinase 1/2 inhibitor PD98059 or p38 kinase inhibitor SB202190 also inhibited the SNP-mediated cell death, suggesting possible requirements of both extracellular signal-related protein kinase 1/2 and p38 kinase for the NO-induced cell death. Furthermore, the selective inhibition of cyclooxygenase (COX)-2 by NS-398 or the inhibition of COX-1/COX-2 by indomethacin blocked the SNP-induced cell death. The chondrocyte death induced by SNP was associated with an overexpression of COX-2 protein (as determined by Western blotting) and an increase in PGE2 release. PD98059 and SB202190, but neither Z-DEVD FMK nor Z-LEHD FMK completely inhibited the SNP-mediated PGE2 production. Analysis of interactions between PGE2 and the cell death showed that PGE2 enhanced the SNP-mediated cell death, whereas PGE2 alone did not induce the chondrocyte death. These data indicate that NO-induced chondrocyte death signaling includes PGE2 production via COX-2 induction and suggest that both extracellular signal-related protein kinase 1/2 and p38 kinase pathways are upstream signaling of the PGE2 production. The results also demonstrate that exogenous PGE2 may sensitize human OA chondrocytes to the cell death induced by NO.

Aged↗
PubMed2005

Allelic imbalance analysis of oral tongue squamous cell carcinoma by high-density single nucleotide polymorphism arrays using whole-genome amplified DNA.

Multiple displacement-based whole-genome DNA amplification is a promising tool to obtain sufficient DNA from small tissue specimens for various genetic analyses, such as SNP array-based analysis. Using Affymetrix 10 K and 100 K SNP mapping array, we evaluated the performance of the Phi29 DNA polymerase-based genome amplification. Greater than 99% concordance in genotyping calls were achieved between amplified and non-amplified DNAs for both arrays. By utilizing the Affymetrix GeneChip Chromosome Copy Number Tool, the allelic imbalance profiles for the advanced stage oral tongue squamous cell carcinoma (OTSCC) were generated based on 10 K and 100 K SNP mapping array results. The results from these two array platforms agree closely, but more precise allelic imbalance patterns can be revealed from the 100 K SNP mapping array data. Furthermore, our data suggested a frequent loss at 3p11-p12 for advanced stage OTSCC.

Allelic Imbalance↗