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ObjectiveTo investigate the relationship between RECK gene polymorphisms and the clinicopathologic features of ameloblastoma.DesignNormal gingival mucosa specimens were obtained from 10 healthy volunteers. Ameloblastomas were surgically removed from 30 patients and part of the tumor specimens were used to detect RECK gene polymorphisms by using PCR-single-strand conformation polymorphism (PCR-SSCP) and DNA sequencing analysis. Expression of RECK and MMP-9 protein was measured using western blot.ResultsThe overall SNP rate was 46.7% (14/30). Four polymorphisms were detected in exon 9, 11, 13, 15 of the RECK gene: two synonymous (P520P and R625R) and two missense SNPs (V275I and I395 V). RECK protein expression in specimens with minor RECK SNPs was lower than that in specimens without RECK SNPs (P < 0.05), and, RECK protein expression in specimens with and without RECK SNPs was lower than that in the normal gingiva specimens (P < 0.05). MMP-9 protein expression in specimens with minor RECK SNPs was higher than that in specimens without RECK SNPs (P < 0.05), and MMP-9 protein expression in specimens with and without RECK SNPs was higher than that in normal gingiva specimens (P < 0.05). RECK gene polymorphisms were closely associated with active proliferation, capsular invasion, and clinical recurrence of ameloblastoma.ConclusionThe rs16932912(G/A) SNP in the RECK gene was closely associated with active proliferation, capsular invasion, and clinical recurrence of ameloblastoma. RECK protein expression was closely associated with the presence of the rs16932912(G/A) SNP.  相似文献   
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Non‐syndromic cleft lip with or without cleft palate (NSCL/P) is a complex disorder, and it results from both of the genetic modifiers and environmental factors, with genetic modifiers contributes to it more than environmental factors. GWASs made great progress in identifying the candidate genes for NSCL/P, but the findings need to be replicated in other populations. In this study, we selected eleven SNPs from recent GWASs and GWAS meta‐analysis to investigate their associations among 308 NSCL/P trios (134 non‐syndromic cleft lip only (NSCLO) trios and 174 non‐syndromic cleft lip with cleft palate (NSCLP) trios) from Han Chinese population. All SNPs were genotyped using SNPscan method and analyzed the data with FBAT, PLINK, and R package. Allelic TDT analysis showed that allele A at rs12543318 was associated with NSCLO trios (= .0032, OR = 0.57, 95% CI: 0.39‐0.83), and parent‐of‐origin effect analysis indicated that allele A at rs12543318 was significantly maternally undertransmitted among NSCLO (P = .0046), which implied the potential influence of genomic imprinting; global TDT further confirmed this association. Individual genotypic TDT showed homozygote C/C at rs12543318 was overtransmitted among NSCLO (Z = 3.79, P = .00015) and NSCL/P groups (Z = 3.83, P = .00013), which indicated that it could increase the risk to have cleft babies. Our findings indicated that rs12543318 was associated with NSCLO from Western Han Chinese population, which will give new scientific evidence for later researches in the etiology of NSOCs.  相似文献   
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Catherine Méplan 《Nutrients》2015,7(5):3621-3651
Mechanistic data have revealed a key role for selenium (Se) and selenoproteins in biological pathways known to be altered in multifactorial diseases, such as cellular maintenance, response to oxidative stress and correct protein folding. Although epidemiological studies indicate that low Se intake is linked to increased risk for various chronic diseases, supplementation trials have given confusing outcomes, suggesting that additional genetic factors could affect the relationship between Se and health. Genetic data support this hypothesis, as risk for several chronic diseases, in particular cancer, was linked to a number of single nucleotide polymorphisms (SNP) altering Se metabolism, selenoprotein synthesis or activity. Interactions between SNPs in selenoprotein genes, SNPs in related molecular pathways and biomarkers of Se status were found to further modulate the genetic risk carried by the SNPs. Taken together, nutritional genomics approaches uncovered the potential implication of some selenoproteins as well as the influence of complex interactions between genetic variants and Se status in the aetiology of several chronic diseases. This review discusses the results from these genetic associations in the context of selenoprotein functions and epidemiological investigations and emphasises the need to assess in future studies the combined contribution of Se status, environmental stress, and multiple or individual SNPs to disease risk.  相似文献   
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The analysis of human population variation is an area of considerable interest in the forensic, medical genetics and anthropological fields. Several forensic single nucleotide polymorphism (SNP) assays provide ancestry-informative genotypes in sensitive tests designed to work with limited DNA samples, including a 34-SNP multiplex differentiating African, European and East Asian ancestries. Although assays capable of differentiating Oceanian ancestry at a global scale have become available, this study describes markers compiled specifically for differentiation of Oceanian populations. A sensitive multiplex assay, termed Pacifiplex, was developed and optimized in a small-scale test applicable to forensic analyses. The Pacifiplex assay comprises 29 ancestry-informative marker SNPs (AIM-SNPs) selected to complement the 34-plex test, that in a combined set distinguish Africans, Europeans, East Asians and Oceanians. Nine Pacific region study populations were genotyped with both SNP assays, then compared to four reference population groups from the HGDP-CEPH human diversity panel. STRUCTURE analyses estimated population cluster membership proportions that aligned with the patterns of variation suggested for each study population’s currently inferred demographic histories. Aboriginal Taiwanese and Philippine samples indicated high East Asian ancestry components, Papua New Guinean and Aboriginal Australians samples were predominantly Oceanian, while other populations displayed cluster patterns explained by the distribution of divergence amongst Melanesians, Polynesians and Micronesians. Genotype data from Pacifiplex and 34-plex tests is particularly well suited to analysis of Australian Aboriginal populations and when combined with Y and mitochondrial DNA variation will provide a powerful set of markers for ancestry inference applied to modern Australian demographic profiles. On a broader geographic scale, Pacifiplex adds highly informative data for inferring the ancestry of individuals from Oceanian populations. The sensitivity of Pacifiplex enabled successful genotyping of population samples from 50-year-old serum samples obtained from several Oceanian regions that would otherwise be unlikely to produce useful population data. This indicates tests primarily developed for forensic ancestry analysis also provide an important contribution to studies of populations where useful samples are in limited supply.  相似文献   
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