Search results for " Polymorphism."
showing 10 items of 1006 documents
VITAMIN D RECEPTOR FOKI AND BSMI POLYMORPHISMS DO NOT SEEM TO BE ASSOCIATED WITH ARTERIAL HYPERTENSION
2014
Polymerase chain reaction analysis of the Xba I polymorphism of the human complement C4 genes provides evidence for strong haplotype conservation.
1995
The genes coding for the two isotypes of the fourth component of human complement, C4A and C4B, are located between the HLA-B and -DR loci of the MHC. We studied the linkage relationship of the previously described XbaI RFLP to obtain further insight into the evolution of the tandemly arranged C4 genes. Using exon-specific PCR amplification followed by restriction analysis and direct DNA sequencing, the polymorphic site could be located in exon 40 of the C4 gene (cDNA position 5095). The polymorphism does not change an amino acid residue. Using nested PCR amplification with isotype-specific primers to amplify either C4A or C4B alleles the haplotype arrangement of the XbaI sites in both isot…
Development and implementation of high-throughput SNP genotyping in barley
2009
Abstract Background High density genetic maps of plants have, nearly without exception, made use of marker datasets containing missing or questionable genotype calls derived from a variety of genic and non-genic or anonymous markers, and been presented as a single linear order of genetic loci for each linkage group. The consequences of missing or erroneous data include falsely separated markers, expansion of cM distances and incorrect marker order. These imperfections are amplified in consensus maps and problematic when fine resolution is critical including comparative genome analyses and map-based cloning. Here we provide a new paradigm, a high-density consensus genetic map of barley based…
Recolonization after habitat restoration leads to decreased genetic variation in populations of a terrestrial orchid.
2012
Colonization is crucial to habitat restoration projects that rely on the spontaneous regeneration of the original vegetation. However, as a previously declining plant species spreads again, the likelihood of founder effects increases through recurrent population founding and associated serial bottlenecks. We related Amplified Fragment Length Polymorphism markers genetic variation and fitness to colonization history for all extant populations of the outcrossing terrestrial orchid Dactylorhiza incarnata in an isolated coastal dune complex. Around 1970, D. incarnata suffered a severe bottleneck yet ultimately persisted and gradually spread throughout the spatially segregated dune slacks, aided…
Identification of a genetic contamination in a commercial mouse strain using two panels of polymorphic markers
2007
Rapid detection of genetic contamination is critical in mouse studies involving inbred strains. During a Quantitative Trait Locus (QTL) study using simple sequence length polymorphism (SSLP) markers, we noticed heterozygosity at some loci of a commercially available inbred C57BL/6N mouse strain, suggesting a contamination by another mouse strain. A panel of 100 single-nucleotide polymorphism (SNP) markers was used to confirm and specify the genetic contamination suspected. Retrospective analyses demonstrated that the contamination took place as early as autumn 2003 and has persisted ever since at a fairly constant level. Contaminating alleles most probably originated from a DBA strain. Our…
Candidate Gene and Genome-Wide Association Studies for Circulating Leptin Levels Reveal Population and Sex-Specific Associations in High Cardiovascul…
2019
Leptin is a hormone crucial in the regulation of food intake and body-weight maintenance. However, the genes and gene variants that influence its plasma levels are still not well known. Results of studies investigating polymorphisms in candidate genes have been inconsistent, and, in addition, very few genome-wide association studies (GWAS) have been undertaken. Our aim was to investigate the genes and gene variants most associated with plasma leptin concentrations in a high-cardiovascular-risk Mediterranean population. We measured plasma leptin in 1011 men and women, and analyzed the genetic factors associated using three approaches: (1) Analyzing the single nucleotide polymorphisms (SNPs) …
Evidence for a common origin of most Friedreich ataxia chromosomes in the Spanish population
1996
Haplotype analysis is a powerful approach to understand the spectrum of mutations accounting for a disease in a homogeneous population. We show that haplotype variation for 10 markers linked to the Friedreich ataxia locus (FRDA) argues in favor of an important mutation homogeneity in the Spanish population, and positions the FRDA locus in the region where it has been recently isolated. We also report the finding of a new single nucleotide polymorphism called FAD1. The new marker shows a very strong linkage disequilibrium with Friedreich ataxia (FA) in both the Spanish and French populations. suggesting the existence of an ancient and widespread FRDA mutations. Inclusion of FAD1 in the exten…
Sex-dependent genetic markers of CYP3A4 expression and activity in human liver microsomes
2007
Objective: To find genetic markers of the individual cytochrome P450 (CYP)3A expression. Methods: A large collection of liver samples phenotyped for CYP3A expression and activity was genotyped for CYP3A variants. Data were analyzed for associations between CYP3A phenotypes and genotypes, and for evidence of recent selection. Results: We report associations between the hepatic CYP3A4 protein expression level, as well as its enzymatic activity, measured as verapamil N-dealkylation, and genetic polymorphisms from two regions within the CYP3A gene cluster. One region is defined by several variants, mostly located within CYP3A7, the other by a single nucleotide polymorphism in intron 7 of CYP3A…
Isolation By Distance (IBD) signals in the deep-water rose shrimp Parapenaeus longirostris (Lucas, 1846) (Decapoda, Panaeidae) in the Mediterranean S…
2013
Abstract The identification of boundaries of genetic demes is one of the major goals for fishery management, and few Mediterranean commercial species have not been studied from a genetic point of view yet. The deep-water rose shrimp Parapenaeus longirostris (Lucas, 1846) is one of the most important components of commercial landings in Mediterranean, its fishery aspects have received much attention, regrettably without any concern for the genetic architecture of its populations. The population structure in the central and eastern Mediterranean Sea (captures from six Italian and two Greek landings) has been analysed on the basis of surveys carried out with mitochondrial and AFLP markers. Dat…
pcaH, a molecular marker for estimating the diversity of the protocatechuate-degrading bacterial community in the soil environment
2007
Microorganisms degrading phenolic compounds play an important role in soil carbon cycling as well as in pesticide degradation. The pcaH gene encoding a key ring-cleaving enzyme of the -ketoadipate pathway was selected as a functional marker. Using a degenerate primer pair, pcaH fragments were cloned from two agricultural soils. Restriction fragment length polymorphism (RFLP) screening of 150 pcaH clones yielded 68 RFLP families. Comparison of 86 deduced amino acid sequences displayed 70% identity to known PcaH sequences. Phylogenetic analysis results in two major groups mainly related to PcaH sequences from Actinobacteria and Proteobacteria phyla. This confirms that the developed primer pai…