Search results for "MUTATION"
showing 10 items of 2830 documents
Coat colours in the Massese sheep breed are associated with mutations in the agouti signalling protein (ASIP) and melanocortin 1 receptor (MC1R) genes
2012
Massese is an Italian dairy sheep breed characterized by animals with black skin and horns and black or apparent grey hairs. Owing to the presence of these two coat colour types, this breed can be considered an interesting model to evaluate the effects of coat colour gene polymorphisms on this phenotypic trait. Two main loci have been already shown to affect coat colour in sheep: Agouti and Extension coding for the agouti signalling protein (ASIP) and melanocortin 1 receptor (MC1R) genes, respectively. The Agouti locus is affected by a large duplication including the ASIP gene that may determine the Agouti white and tan allele (A(Wt)). Other disrupting or partially inactivating mutations ha…
Intronic L1 insertion and F268S, novel mutations in RPS6KA3 (RSK2) causing Coffin-Lowry syndrome
2003
Two novel mutations of the ribosomal S6 kinase 2 gene (also known as RSK2) have been identified in two unrelated patients with Coffin–Lowry syndrome. The first mutation consists of a de novo insertion of a 5′-truncated LINE-1 element at position −8 of intron 3, which leads to a skipping of exon 4, leading to a shift of the reading frame and a premature stop codon. The L1 fragment (2800 bp) showed a rearrangement with a small deletion, a partial inversion of the ORF 2, flanked by short direct repeats which duplicate the acceptor splice site. However, cDNA analysis of the patient shows that both sites are apparently not functional. The second family showed the nucleotide change 803T>C in exon…
SARS-CoV-2 genome surveillance in Mainz, Germany, reveals convergent origin of the N501Y spike mutation in a hospital setting
2021
AbstractWhile establishing a regional SARS-Cov-2 variant surveillance by genome sequencing, we have identified three infected individuals in a clinical setting (two long-term hospitalized patients and a nurse) that shared the spike N501Y mutation within a genotype background distinct from the current viral variants of concern. We suggest that the adaptive N501Y mutation, known to increase SARS-CoV-2 transmissibility, arose by convergent evolution around December in Mainz, Germany. Hospitalized patients with a compromised immune system may be a potential source of novel viral variants, which calls for monitoring viral evolution by genome sequencing in clinical settings.
Desmin‐related Myopathies
2006
Outstanding progress in elucidating the pathology of muscular disorders at light and electron microscopic levels has allowed the identification of proteins involved in pathological alterations. This, in turn, has led to discoveries of multiple genes and mutations associated with previously poorly understood conditions. An unexpected result is that phenotypically similar and pathogenetically related neuromuscular disorders are associated with mutations in one or the other of several interacting proteins. Keywords: desmin-related myopathy; distal myopathy; cardiomyopathy; desmin and alpha-B crystallin gene mutations; functional analysis; molecular pathogenesis; genotype–phenotype correlations
The impact of next-generation sequencing technology on preimplantation genetic diagnosis and screening.
2013
Largely because of efforts required to complete the Human Genome Project, DNA sequencing has undergone a steady transformation with still-ongoing developments of high-throughput sequencing machines for which the cost per reaction is falling drastically. Similarly, the fast-changing landscape of reproductive technologies has been improved by genetic approaches. Preimplantation genetic diagnosis and screening were established more than two decades ago for selecting genetically normal embryos to avoid inherited diseases and to give the highest potential to achieve stable pregnancies. Most recent additions to the IVF practices (blastocyst/trophectoderm biopsy, embryo vitrification) and adoption…
Detection of mammalian carcinogens with an immunological DNA synthesis-inhibition test.
1992
There is a close relationship between genotoxicity, mutagenicity and carcinogenicity. But the controversy of which short-term test system best recognizes human carcinogens is still going on. Currently, the Salmonella gene mutation assay ('Ames test') is the most widely used test for the screening of mutagens. However, many in vitro tests hold unsatisfactory validity data, presumably because of the inability of present short-term tests to detect non-genotoxic carcinogens, which are increasingly being brought into focus in the discussions of genesis of cancer. One principle often neglected in this context is the property of genotoxic agents to inhibit replicative DNA synthesis in (proliferati…
A Novel Homozygous Mutation in the Solute Carrier Family 26 Member 7 Gene Causes Thyroid Dyshormonogenesis in a Girl with Congenital Hypothyroidism
2020
We investigated the genetic cause of thyroid dyshormonogenesis in a girl with congenital hypothyroidism. Genetic analysis showed that she was homozygous for a hitherto not described mutation (c.1432_1433delGT, p.V478KfsX11) in the solute carrier family 26 member 7 (SLC26A7) gene. SLC26A7 is proposed to be an anion transporter in the thyroid gland. The mutation leads to a frameshift and a premature stop codon. The predicted protein is truncated and very likely to be nonfunctional if it was expressed at all. In addition, in silico studies predict the mutation to be pathogenic.
Familial combined hypolipidemia due to mutations in the ANGPTL3 gene
2013
The role of ANGPTL3 in lipoprotein metabolism emerged from studies in a mutant mouse strain characterized by severe hypotriglyceridemia and carrying a loss-of-function (LOF) mutation of the ANGPTL3 gene. ANGPTL3 was found to inhibit lipoprotein lipase and endothelial lipase. Genome-wide association studies in humans demonstrated the association of ANGPTL3 variants with plasma triglyceride levels and LOF mutations of ANGPTL3 were found in hypotriglyceridemic subjects in population studies. Recently, individuals originally classified as affected by familial hypobetalipoproteinemia were found to be homozygotes/compound heterozygotes for rare LOF mutations of ANGPTL3. They show a striking reduc…
Structural mapping of GABRB3 variants reveals genotype-phenotype correlations
2021
AbstractPurposePathogenic variants in GABRB3 have been associated with a spectrum of phenotypes from severe developmental disorders and epileptic encephalopathies to milder epilepsy syndromes and mild intellectual disability. In the present study, we analyzed a large cohort of individuals with GABRB3 variants to deepen the phenotypic understanding and investigate genotype-phenotype correlations.MethodsThrough an international collaboration, we analyzed electro-clinical data of unpublished individuals with variants in GABRB3 and we reviewed previously published cases. All missense variants were mapped onto the 3D structure of the GABRB3 subunit and clinical phenotypes associated with the dif…
The human complement C9 gene: structural analysis of the 5′ gene region and genetic polymorphism studies
2001
Summary C9 is the last of the human complement components creating the membrane attack complex. The single chain serum protein is encoded by a gene located on chromosome 5p13 that is composed of 11 exons. With the aid of inverse PCR, the hitherto unknown regions flanking exon 1 and the 3′ part of exon 11 (3′UTR) have been sequenced. A computer-based analysis of the 300-bp region located just upstream of the AUG start codon showed homologies to known DNA modules which affect the transcriptional regulation of certain genes. The most striking of these is a sequence that may substitute the missing TATA box in initiating C9 transcription. In the 3′UTR, three successive polyadenylation signals we…