Search results for "Genetic algorithm"

2019

Codon composition, GC content and local RNA secondary structures can have a profound effect on gene expression, and mutations affecting these parameters, even though they do not alter the protein sequence, are not neutral in terms of selection. Although evidence exists that, in some cases, selection favours more stable RNA secondary structures, we currently lack a concrete idea of how many genes are affected within a species, and whether this is a universal phenomenon in nature. We searched for signs of structural selection in a global manner, analysing a set of 1 million coding sequences from 73 species representing all domains of life, as well as viruses, by means of our newly developed s…

Autosomal dominant Brown–Vialetto–Van Laere syndrome with UBQLN1 mutation

2013

Mutation in candidate genes account for a small minority of hypobetalipoproteinemias and NGS analysis support polygenicity in mutation-negative patie…

2020

Molecules and Morphology, Phylogenetics and Genetics

1994

Various explanations can be offered for the incongruence between phylogenetic hypotheses resulting from morphological and molecular data sets. Of these, the possibility that incongruence may result from the mutation of major morphogenetic genes leading to dramatic morphological divergence unaccompanied by equivalent change of the phylogenetic marker molecule(s) used is discussed in detail. As evidence for this hypothesis, several examples for such incongruence are surveyed. It seems possible that in many cases the genetic basis of the morphological characters responsible for the incongruence found may be simple, and that the genes involved may be homologous to genes known from mutant system…

Changes in chromosomal polymorphism when selecting for a neutral trait inDrosophila subobscura

1986

The changes which occurred in the chromosomal polymorphism ofDrosophila subobscura when selecting for abdominal bristle number were analysed. A decrease in the diversity of arrangements and an increase in homozygosity over the selection experiment were found. These changes were stronger in selection than in control lines.

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…

Inbreeding, energy use and condition

2009

In energetic terms, fitness may be seen to be dependent on successful allocation of energy between life-history traits. In addition, fitness will be constrained by the energy allocation ability, which has also been defined as condition. We suggest here that the allocation ability, estimated as the difference between total energy budget and maintenance metabolism, may be used as a measure of condition. We studied this possibility by measuring the resting metabolic rate and metabolism during forced exercise in Gryllodes sigillatus crickets. To verify that these metabolic traits are closely related to fitness, we experimentally manipulated the degree of inbreeding of individuals belonging to t…

Mitochondrial DNA variations in patients with Type 2 (non-insulin dependent) diabetes mellitus and a Welsh control population

1999

The LDL-receptor gene point mutation FH-Genoa/Palermo is the most frequent mutation responsible for Familial Hypercholesterolemia in Sicily. The mutation does not introduce or abolish any useful restriction site. We establish a GeneComb-based strategy to identify this mutation in a population of Sicilian unrelated clinically diagnosed FH probands. The method was very sensitive and specific; 12 out of 90 (13.3%) unrelated FH probands were found to carry the FH-Genoa/Palermo mutation. According to these results, the FH-Genoa/Palermo is the more frequent LDL-receptor gene mutation among the Sicilian FH patients. Moreover FH-Genoa/Palermo is the mutation cluster to date more represented in Sout…

Assignment of signal transducer and activator of transcription 5A (STAT5A) to porcine chromosome 12p13→p11 by radiation hybrid panel mapping

2005

Direct evidence for positive selection of skin, hair, and eye pigmentation in Europeans during the last 5,000 y

2014

Significance Eye, hair, and skin pigmentation are highly variable in humans, particularly in western Eurasian populations. This diversity may be explained by population history, the relaxation of selection pressures, or positive selection. To investigate whether positive natural selection is responsible for depigmentation within Europe, we estimated the strength of selection acting on three genes known to have significant effects on human pigmentation. In a direct approach, these estimates were made using ancient DNA from prehistoric Europeans and computer simulations. This allowed us to determine selection coefficients for a precisely bounded period in the deep past. Our results indicate t…