Search results for "FREQUENCY"

The genetic structure of Drosophila subobscura populations from the islands of Majorca and Minorca (Balearic Islands, Spain) based on allozymes and m…

1999

The genetic structure of seven populations of Drosophila subobscura from different locations on Majorca and Minorca (Balearic Islands, Spain) was studied using two types of markers: allozyme and mitochondrial DNA restriction analyses. Both markers showed congruent results. In the allozyme data, when the Acph-1 locus was excluded from the joint FST statistics, only three out of 21 comparisons were statistically significant, lending support to the hypothesis of low genetic differentiation. The mtDNA restriction analyses showed two haplotypes at a high frequency (more than 40% each), irrespective of the location considered, and a number of endemic haplotypes at very low frequencies (not higher…

Mutated tumor alleles are expressed according to their DNA frequency

2014

AbstractThe transcription of tumor mutations from DNA into RNA has implications for biology, epigenetics and clinical practice. It is not clear if mutations are in general transcribed and, if so, at what proportion to the wild-type allele. Here, we examined the correlation between DNA mutation allele frequency and RNA mutation allele frequency. We sequenced the exome and transcriptome of tumor cell lines with large copy number variations, identified heterozygous single nucleotide mutations and absolute DNA copy number and determined the corresponding DNA and RNA mutation allele fraction. We found that 99% of the DNA mutations in expressed genes are expressed as RNA. Moreover, we found a hig…

Frequencies of pseudocholinesterase variants in Icelanders, Greeks and Pakistanis.

1968

THE formation of the human pseudocholinesterase variants is controlled by at least four alleles at one autosomal locus termed E1 (ref. 1). The four alleles are , , and (refs. 2–5). The heterozygotes have been found in remarkably uniform frequencies, about 3 to 6 per cent, in Caucasians from Europe and North America3,8–11, and also in Australian aborigines12 and Mexican Indians13, but are relatively rare among Negroes11 and Mongoloids10,11,14.

Genome-wide significant association with seven novel multiple sclerosis risk loci

2015

Objective A recent large-scale study in multiple sclerosis (MS) using the ImmunoChip platform reported on 11 loci that showed suggestive genetic association with MS. Additional data in sufficiently sized and independent data sets are needed to assess whether these loci represent genuine MS risk factors. Methods The lead SNPs of all 11 loci were genotyped in 10 796 MS cases and 10 793 controls from Germany, Spain, France, the Netherlands, Austria and Russia, that were independent from the previously reported cohorts. Association analyses were performed using logistic regression based on an additive model. Summary effect size estimates were calculated using fixed-effect meta-analysis. Results…

Cis-epistasis at the LPA locus and risk of cardiovascular diseases.

2022

AIMS Coronary artery disease (CAD) has a strong genetic predisposition. However, despite substantial discoveries made by genome-wide association studies (GWAS), a large proportion of heritability awaits identification. Non-additive genetic-effects might be responsible for part of the unaccounted genetic variance. Here we attempted a proof-of-concept study to identify non-additive genetic effects, namely epistatic interactions, associated with CAD. METHODS AND RESULTS We tested for epistatic interactions in ten CAD case-control studies and UK Biobank with focus on 8,068 SNPs at 56 loci with known associations with CAD risk. We identified a SNP pair located in cis at the LPA locus, rs1800769 …

Frequency of the HFE Gene Mutations in Five Italian Populations

2002

Abstract ABSTRACT Genetic hemochromatosis is an autosomal recessive disorder characterized by iron overload and a variety of clinical manifestations such as liver cirrhosis and arthropathy. It is the most common genetic disease of northern European populations. The principal gene responsible for hereditary hemochromatosis, designated HFE, is located on chromosome 6 in the HLA region. The single point mutation 845A, changing cysteine at position 282 to tyrosine (C282Y), in this gene has been identified as the main genetic basis of hereditary hemochromatosis. Two other mutations, 187G, a histidine to aspartate at amino acid 63 (H63D), and 193T, a serine to cysteine at amino acid 65 (S65C), ap…

Studies on the population genetics of the ceruloplasmin polymorphism

1969

Phenotype and gene frequencies of the ceruloplasmin polymorphism are reported. In all populations considered here (Germans, Icelanders, Iranians, Pakistani, and Koreans) high frequencies of the allele CpB (0.978–0.996) could be observed, whilst the frequencies of the alleles CpA (0.003–0.013) and CpC (0.000–0.013) are very low.

Polymorphism of phosphoglucomutase in a German breed cattle

2009

Summary Haemolysates from cattle belonging to the Hochfleckvieh breed (N = 42), were studied for electrophoretic variation of phosphoglucomutase. Three phenotypes were observed which could be explained on the basis of two alleles PGMiA and PGMiB. The PGM'B frequency of 0.7325 is comparatively lower than in other breeds.

A new polymorphism in the human HFE gene

1999

On the population genetics of the ceruloplasmin polymorphism

1972

The frequencies of Cp-variants in 3 European, 1 Asiatic and 3 African populations are reported. The most striking fact is the high incidence of the CpA-allele not only in the African but also in 2 European samples.