Search results for "LOD"
showing 10 items of 4833 documents
Intergenomic interactions affect female reproduction: evidence from introgression and inbreeding depression in a haplodiploid mite
2004
Nuclear and cytoplasmic genomes can coevolve antagonistically or harmoniously to affect fitness. One commonly used test for nuclear-cytoplasmic coadaptation relies on the breakup of coadapted gene complexes by introgression, potentially resulting in an increased frequency of nuclear alleles in deleterious interaction with an alien cytoplasm. We investigated the phenotypic effect of such genes on female reproduction in outbred and inbred introgressed lines of the haplodiploid mite Tetranychus urticae. Introgression changed female lifetime fecundity and increased male production, in ways suggesting a control of fecundity by nuclear genes. Conversely introgression reduced the fertilization rat…
Evaluation of a susceptibility gene for schizophrenia on chromosome 6p by multipoint affected sib-pair linkage analysis
1995
The influence of genetic factors in schizophrenia has been convincingly demonstrated by family, twin and adoption studies, but the mode of transmission remains uncertain. The reported pattern of recurrence risks suggests a set of interacting loci. Based on prior evidence for linkage on chromosome 6p (K. Kendler, pers. comm.), we have scanned the short arm of chromosome 6 in 54 families for loci predisposing to schizophrenia, using 25 microsatellite markers spanning 60 centiMorgans (cM). Allele sharing identity by descent was examined in affected sib-pairs from these families, followed by multipoint sib-pair linkage analysis. Positive lod scores were obtained over a wide region (D6S470 to D6…
Similar Performance of Diploid and Haploid Males in an Ant Species without Inbreeding Avoidance
2013
AbstractUnder haplodiploidy, a characteristic trait of all Hymenoptera, femalesdevelop from fertilised eggs, and males from unfertilised ones. Males aretherefore typically haploid. Yet, inbreeding can lead to the production ofdiploid males that often fail in development, are sterile or are of lowerfertility. In most Hymenoptera, inbreeding is avoided by dispersal flightsof one or both sexes, leading to low diploid male loads. We investigatedcauses for the production of diploid males and their performance in ahighly inbred social Hymenopteran species. In the ant Hypoponera opacior,inbreeding occurs between wingless sexuals, which mate within themother nest, whereas winged sexuals outbreed dur…
Evolutionary analysis of Citrus tristeza virus outbreaks in Calabria, Italy: two rapidly spreading and independent introductions of mild and severe i…
2014
The evolution of citrus tristeza virus (CTV) from outbreaks occurred in Calabria, Italy, was compared with that of CTV outbreaks reported previously in another two proximal Italian regions, Sicily and Apulia. Examination of four genomic regions (genes p20, p25 and p23, and one fragment of open reading frame 1) showed two recombination events, and phylogenetic analysis disclosed two divergent CTV groups in Calabria: one formed by severe and the other by mild isolates. This analysis, together with others involving population genetic parameters, revealed a low migration rate of CTV between the three Italian regions, as well as significant differences in selective pressures, epidemiology and de…
Isolation and characterization of 11 polymorphic trinucleotide microsatellite markers in the stonefly Arcynopteryx compacta (Plecoptera: Perlodidae).
2011
We describe the isolation of 11 polymorphic trinucleotide microsatellite loci from the stonefly Arcynopteryx compacta. Loci were highly variable with 3 to 14 alleles (mean = 6.45). Observed heterozygosity ranged from 0 to 0.867. Seven loci showed significant deviation from Hardy–Weinberg equilibrium across both populations. There was no evidence for null alleles, and thus, Hardy–Weinberg departures could have resulted from genetic structure between populations or subpopulations. No linkage between loci was found. The 11 loci should prove highly informative for population genetic studies.
Search forReCQL4mutations in 39 patients genotyped for suspected Rothmund-Thomson/Baller-Gerold syndromes
2014
Three overlapping conditions, namely Rothmund-Thomson (RTS), Baller-Gerold (BGS) and RAPADILINO syndromes, have been attributed to RECQL4 mutations. Differential diagnoses depend on the clinical presentation, but the numbers of known genes remain low, leading to the widespread prescription of RECQL4 sequencing. The aim of our study was therefore to determine the best clinical indicators for the presence of RECQL4 mutations in a series of 39 patients referred for RECQL4 molecular analysis and belonging to the RTS (27 cases) and BGS (12 cases) spectrum. One or two deleterious RECQL4 mutations were found in 10/27 patients referred for RTS diagnosis. Clinical and molecular reevaluation led to a…
Genomic structure and paralogous regions of the inversion breakpoint occurring between human chromosome 3p12.3 and orangutan chromosome 2.
2003
Intrachromosomal duplications play a significant role in human genome pathology and evolution. To better understand the molecular basis of evolutionary chromosome rearrangements, we performed molecular cytogenetic and sequence analyses of the breakpoint region that distinguishes human chromosome 3p12.3 and orangutan chromosome 2. FISH with region-specific BAC clones demonstrated that the breakpoint-flanking sequences are duplicated intrachromosomally on orangutan 2 and human 3q21 as well as at many pericentromeric and subtelomeric sites throughout the genomes. Breakage and rearrangement of the human 3p12.3-homologous region in the orangutan lineage were associated with a partial loss of dup…
Humans and chimpanzees differ in their cellular response to DNA damage and non-coding sequence elements of DNA repair-associated genes.
2008
Compared to humans, chimpanzees appear to be less susceptible to many types of cancer. Because DNA repair defects lead to accumulation of gene and chromosomal mutations, species differences in DNA repair are one plausible explanation. Here we analyzed the repair kinetics of human and chimpanzee cells after cisplatin treatment and irradiation. Dot blots for the quantification of single-stranded (ss) DNA repair intermediates revealed a biphasic response of human and chimpanzee lymphoblasts to cisplatin-induced damage. The early phase of DNA repair was identical in both species with a peak of ssDNA intermediates at 1 h after DNA damage induction. However, the late phase differed between specie…
Tipogrāfs Gerhards Šrēders un latīņu okazionālā dzeja
2019
Rakstā atainota Rīgas pilsētas otrā tipogrāfa Gerharda Šrēdera (Gerhard Schröder, ?-1657) darbības vide un dzīvesgājums. Vispirms iezīmēti grāmatiespiešanas pirmsākumi Rīgā, tipogrāfa pienākumi, pasūtījumu klāsts, atlīdzība par darbu un iegūstamās privilēģijas. Tad aplūkoti priekšnoteikumi, kas Gerhardam Šrēderam bija jāizpilda, lai iegūtu Rātes atļauju pārņemt darbu Nikolaja Mollīna (Niclaes Mollijns, ap 1550/1555-1625) spiestuvē. Tipogrāfijas kvalitātes un iespieddarbu specifikas raksturošanai pētīti okazionālās dzejas iespieddarbi: apskatīts poligrāfiskais izpildījums (vienā iespieddarbā izmantoto dažādo izmēru un veidu burtu komplektu skaits, dekoratīvo elementu, kokgrebumu un gravīru p…