Search results for "Zygosity"
showing 10 items of 200 documents
WWOX, a Chromosomal Fragile Site Gene and its Role in Cancer
2006
Allelic imbalances affecting the long arm of chromosome 16 have been extensively reported in the literature as common abnormalities observed in various carcinoma types, As a result of loss of heterozygosity (LOH) studies in breast cancer, we delimited a genomic area within chromosome 16 that demonstrated the highest frequency of abnormalities. This led us to the identification and cloning of WWOX, a candidate tumor suppressor gene (TSG) that spans a fragile region of DNA located at 16q23.3-24.1 (FRA16D: the second most active common chromosomal fragile site in the human genome). This gene encodes a protein that contains two WW domains responsible of protein-protein interactions and a short-…
Autosomal recessive mutations inTHOC6cause intellectual disability: syndrome delineation requiring forward and reverse phenotyping
2016
THOC6 is a part of the THO complex, which is involved in coordinating mRNA processing with export. The THO complex interacts with additional components to form the larger TREX complex (transcription export complex). Previously, a homozygous missense mutation in THOC6 in the Hutterite population was reported in association with syndromic intellectual disability. Using exome sequencing, we identified three unrelated patients with bi-allelic mutations in THOC6 associated with intellectual disability and additional clinical features. Two of the patients were compound heterozygous for a stop and a missense mutation, and the third was homozygous for a missense mutation; the missense mutations wer…
Independence between developmental stability and canalization in the skull of the house mouse.
2000
The relationship between the two components of developmental homeostasis, that is canalization and developmental stability (DS), is currently debated. To appraise this relationship, the levels and morphological patterns of interindividual variation and fluctuating asymmetry were assessed using a geometric morphometric approach applied to the skulls of laboratory samples of the house mouse. These three samples correspond to two random-bred strains of the two European subspecies of the house mouse and their F1 hybrids. The inter- and intraindividual variation levels were found to be smaller in the hybrid group compared to the parental ones, suggesting a common heterotic effect on skull canali…
Microspore embryogenesis induced through in vitro anther culture of almond (Prunus dulcis Mill.)
2016
Anther culture is one of the most widely used methods to induce gametic embryogenesis. The aim of this investigation was to induce microspore embryogenesis in almond (Prunus dulcis Mill.), through this technique. Anthers were cultured at the vacuolated developmental stage, and seven cultivars, two culture media and two temperature treatments were assessed. Although evidence of the microspore induction was observed in all the genotypes and treatments tested (symmetrical nucleus division and multinucleated structures), calli were produced merely by anthers cultured in the medium P and the regeneration of embryos was detected only in anthers of the cultivars Filippo Ceo, Lauranne and Genco, pl…
THE EFFECTS OF MATING SYSTEM AND GENETIC VARIABILITY ON SUSCEPTIBILITY TO TREMATODE PARASITES IN A FRESHWATER SNAIL, LYMNAEA STAGNALIS
2004
The amount and distribution of genetic variability in host populations can have significant effects on the outcome of host-parasite interactions. We studied the effect of mating system and genetic variability on susceptibility of Lymnaea stagnalis snails to trematode parasites. Mating system of snails from eight populations differing in the amount of genetic variability was manipulated, and self- and cross-fertilized offspring were exposed to naturally occurring trematode parasites in a controlled lake experiment. Susceptibility of snails varied between populations, but mating-system treatment did not have a significant effect. Heterozygosity of snails was negatively correlated with the pro…
Genetic polymorphism in dopamine receptor D4 is associated with early body condition in a large population of greater flamingos,Phoenicopterus roseus
2012
Body condition is an important determinant of fitness in many natural populations. However, as for many fitness traits, the underlying genes that regulate body condition remain elusive. The dopamine receptor D4 gene (DRD4) is a promising candidate as dopamine is known to play an important role in the regulation of food intake and the metabolism of both glucose and lipids in vertebrates. In this study, we take advantage of a large data set of greater flamingos, Phoenicopterus roseus, to test whether DRD4 polymorphism predicts early body condition (EBC) while controlling for whole-genome effects of inbreeding and outbreeding using microsatellite multilocus heterozygosity (MLH). We typed 670 o…
Somatic loss of an EXT2 gene mutation during malignant progression in a patient with hereditary multiple osteochondromas
2015
Multiple osteochondromas (MO) is an autosomal-dominant skeletal disorder caused by mutations in the exostosin-1 ( EXT1 ) or exostosin-2 ( EXT2 ) genes. In this study, we report the analysis of the mutational status of the EXT2 gene in tumor samples derived from a patient affected by hereditary MO, documenting the somatic loss of the germline mutation in a giant chondrosarcoma and in a rapidly growing osteochondroma. The sequencing of all exons and exon–intron junctions of the EXT1 and EXT2 genes from blood DNA of the proband did not reveal any mutation in the EXT1 gene but did demonstrate the presence of the transition point mutation c.67C > T in the EXT2 gene, determining the introduction …
The influence of land use on the genetic structure of populations of the common frog Rana temporaria
1990
In order to find out the influence of land use and topographic distance on the genetic structure of populations of the common frog Rana temporaria L. in the Saar-Palatinate lowlands (Federal Republic of Germany), tissue of larvae was examined by means of horizontal starch gel electrophoresis. A total of 24 loci coding for 14 different enzymes were studied. Genotype frequencies, allele frequencies and mean heterozygosity were calculated, and genetic distances using Nei's formula. Strong deviations from the Hardy-Weinberg equilibrium were found; the degree of homozygosity was higher than expected. Separation by highways reduced average heterozygosity as well as genetic polymorphism of local p…
Isolation of seven polymorphic microsatellites in Ophioblennius atlanticus atlanticus (Perciformes, Blenniidae)
2005
We isolated and characterized seven polymorphic microsatellite loci of Ophioblennius atlanticus atlanticus (Valenciennes, 1836) using an optimized protocol to construct and screen a microsatellite-enriched genomic library. The analysis of variability was performed in 16 specimens from Faial Island (Azores, Portugal). The mean number of alleles was 8.71 ± ± ± 2.43 and the level of expected heterozygosity ranged from 0.764 to 0.903. The total exclusionary probabilities using these loci for the first and the second parent were 0.985 and 0.998, respectively, suggesting that these microsatellites are a useful tool for large-scale parentage analysis.
A New Mutation of the p53 Gene in Human Neuroblastoma, Not Correlated with N-myc Amplification
1999
N-myc gene amplification and/or loss of heterozygosity of chromosome 1 (LOH lp) are important criteria for prognosis and progression in human neuroblastoma (NB). Despite the high incidence of alterations of the p53 gene in human cancers, very few p53 mutations have been reported in NB. The objective of our study was to search for p53 mutations in NB and their correlation with N-myc amplification and clinical or pathologic parameters. We analyzed 14 selected cases of NB from the Spanish Protocol N-II-92. We found a missense mutation in codon 248 CGG to GGG (Arg/Gly) in one case of stage 4 NB with no N-myc amplification. Our results confirm the low incidence of p53 gene mutation in neuroblas…