Search results for "MUTATION"
showing 10 items of 2830 documents
Novel SERPING1 mutation causing Hereditary Angioedema in a Brazilian family
2009
Retinoblastoma: implicaciones del estudio genético-molecular
2006
Indication of a common origin of German and American Families with Familial Amyloidneuropathy Typ II
1999
Abstract The classification of familial amyloid neuropathies (FAP) is traditionally based on clinical and regional aspects. In the last 10 years more than 40 mutations of the transthyretin gene have been found to be responsible for different clinical forms of amyloidosis including familial FAP.FAP II is caused by a mutation on the codon 58 of the transthyretin gene. Only two american kindreds (the Maryland/German and the Ohio family) have previously been reported with FAP II starting in the 3rd or 4th decade by sensory disturbances of the hands typically as a carpal tunnel syndrome. We report on a german family with FAP II from the rhine river area south of Mainz. Four members with typical …
Novel <b><i>VANGL1</i></b> Gene Mutations in 144 Slovakian, Romanian and German Patients with Neural Tube Defects
2012
Neural tube defects (NTDs) are a group of congenital malformations of the central nervous system occurring at an average rate of 1 per 1,000 human pregnancies worldwide. Numerous genetic and environmental factors are discussed to be relevant in their etiology. In mice, mutants in >200 genes including the planar cell polarity (PCP) pathway are known to cause NTDs, and recently, heterozygous mutations in the human <i>VANGL1</i> gene have been described in a small subset of patients with NTDs. We performed a <i>VANGL1</i> mutation analysis in 144 unrelated individuals with NTDs from Slovakia, Romania and Germany and identified 3 heterozygous missense mutations: c.613…
A comparison of two indirect methods for estimating average levels of gene flow using microsatellite data.
1999
We compare the performance of Nm estimates based on FST and RST obtained from microsatellite data using simulations of the stepwise mutation model with range constraints in allele size classes. The results of the simulations suggest that the use of microsatellite loci can lead to serious overestimations of Nm, particularly when population sizes are large (N5000) and range constraints are high (K20). The simulations also indicate that, when population sizes are small (N/= 500) and migration rates are moderate (Nm approximately 2), violations to the assumption used to derive the Nm estimators lead to biased results. Under ideal conditions, i.e. large sample sizes (ns/= 50) and many loci (nl/=…
Gene encoding capsid protein VP1 of foot-and-mouth disease virus A quasispecies model of molecular evolution
1988
A phylogenetic tree relating the VP1 gene of 15 isolates of foot-and-mouth disease virus (FMDV) of serotypes A, C, and O has been constructed. The most parsimonious tree shows that FMDV subtypes and isolates within subtypes constitute sets of related, nonidentical genomes, in agreement with a quasispecies mode of evolution of this virus. The average number of nucleotide replacements per site for all possible pairs of VP1 coding segments is higher among representatives of serotype A than serotype C or O. In comparing amino acid sequences, the values of dispersion index (variance/mean value) are greater than 1, with the highest values scored when all sequences are considered. This indicates a…
Following the very initial growth of biological RNA viral clones
2005
Due to their extremely high genetic diversity, which is a direct consequence of high mutation rates, RNA viruses are often described as molecular quasispecies. According to this theory, RNA virus populations cannot be understood in terms of individual viral clones, as they are clouds of interconnected mutants, but this prediction has not yet been demonstrated experimentally. The goal of this study was to determine the fitness of individual clones sampled from a given RNA virus population, a necessary previous step to test the above prediction. To do so, limiting dilutions of a vesicular stomatitis virus population were employed to isolate single viral clones and their initial growth dynamic…
Viral mutation and substitution: units and levels.
2011
Viruses evolve within a hierarchy of organisational levels, from cells to host species. We discuss how these nested population structures complicate the meaning and interpretation of two apparently simple evolutionary concepts: mutation rate and substitution rate. We discuss the units in which these fundamental processes should be measured, and explore why, even for the same virus, mutation and substitution can occur at very different tempos at different biological levels. In addition, we explore the ability of whole genome evolutionary analyses to distinguish between natural selection and other population genetic processes. A better understanding of the complexities underlying the molecula…
An approach to determining anthocyanin synthesis enzyme gene expression in an evolutionary context: an example from Erica plukenetii
2019
Abstract Background and Aims Floral colour in angiosperms can be controlled by variations in the expression of the genes of the anthocyanin pathway. Floral colour shifts influence pollinator specificity. Multiple shifts in floral colour occurred in the diversification of the genus Erica (Ericaceae), from plesiomorphic pink to, for example, red or white flowers. Variation in anthocyanin gene expression and its effects on floral colour in the red-, pink- and white-flowered Erica plukenetii species complex was investigated. Methods Next generation sequencing, reverse transcriptase PCR and real-time reverse transcriptase quantitative PCR were used to quantify anthocyanin gene expression. Key Re…
In vitro genome editing using CRISPR/Cas9 to edit SERPINA1 PiZ mutation
2019
Introduction: The emergence some years ago of the CRISPR/Cas9 system allowed gene therapy to be specific, versatile, cheap and approachable to almost every laboratory. Due to these features, many different genetic diseases such as cystic fibrosis or β-thalassemia have been addressed in cellular models using the CRISPR/Cas9 genetic editing tool. Alpha-1 antytripsin deficiency (AATD) is a rare genetic condition that can provoke respiratory and hepatic symptoms. The Z allele of SERPINA1 gene is a well-characterised point mutation that can trigger the whole pathology. Henceforth, Z mutation is a suitable target for genetic edition using CRISPR/Cas9 in order to develop a gene therapy to treat AA…