Search results for "LOCUS"
showing 10 items of 632 documents
Basic issues in forensic DNA typing
1997
DNA analysis has become the standard method in forensic stain typing (termed DNA profiling). In contrast to conventional serological methods, any human tissue or body fluid can be analysed by DNA profiling as long as it contains nucleated cells. The majority of genetic systems studied at the DNA level are derived from "non-coding" portions from the human genome, and are located either in the vicinity of expressed (coding) genes or in stretches of DNA sequences interspersing with the genes. The typing results are usually recorded as DNA fragment lengths or "alleles" indicating the number of core repeat elements for short tandem repeat systems. These typing results do not contain any useful i…
Polymorphism and chromosomal localization of the porcine signal transducer and activator of transcription 5B gene (STAT5B).
2006
Signal transducers and activators of transcription (STATs) are a family of transcription factors. STAT5A and 5B are two highly related proteins encoded by two distinct genes. Transgenic knockout mice studies have indicated the importance of STAT5 proteins for the regulation of both lactation and growth performance. Moreover, different studies determine the role of STAT5 proteins in the modulation of adipocyte function. In this study, we sequenced one fragment of STAT5B gene from animals of six breeds (Duroc, Iberian, Landrace, Large White, Pie´train and Meishan) to identify genetic variants. A G/A single nucleotide polymorphism in intron 14 creates a polymorphic PstI restriction site and wa…
Characterization of mutations and sequence variations in complex STR loci by second generation sequencing
2013
Abstract We used second generation sequencing (SGS) to examine sequence variation and mutational patterns in complex STR loci in Danish paternity cases. Four STR loci, D2S1338, D3S1358, D12S391 and D21S11, were sequenced in 45 samples from 15 confirmed trios with genetic inconsistencies between one of the parents and the child in either the D2S1338 or the D3S1358 loci. In 12 of the 15 cases, SGS revealed the allele that had mutated from the parent. In total, 61 different alleles were found in the 30 unrelated individuals. The highest variation was observed in the D12S391 locus and the lowest one in the D3S1358 locus. The four STR loci are good candidate loci for future SGS kits for forensic…
Structural characterization of chromosome I size variants from a natural yeast strain
2002
Many yeast strains isolated from the wild show karyotype instability during vegetative growth, with rearrangement rates of up to 10(-2) chromosomal changes per generation. Physical isolation and analysis of several chromosome I size variants of one of these strains revealed that they differed only in their subtelomeric regions, leaving the central 150 Kb unaltered. Fine mapping of these subtelomeric variable regions revealed gross alterations of two very similar loci, FLO1 and FLO9. These loci are located on the right and left arms, respectively, of chromosome I and encompass internal repetitive DNA sequences. Furthermore, some chromosome I variants lacking the FLO1 locus showed evidence of…
COMPARING EVOLVABILITIES: COMMON ERRORS SURROUNDING THE CALCULATION AND USE OF COEFFICIENTS OF ADDITIVE GENETIC VARIATION
2012
In 1992, David Houle showed that measures of additive genetic variation standardized by the trait mean, CVA (the coefficient of additive genetic variation) and its square (IA), are suitable measures of evolvability. CVA has been used widely to compare patterns of genetic variation. However, the use of CVAs for comparative purposes relies critically on the correct calculation of this parameter. We reviewed a sample of quantitative genetic studies, focusing on sire models, and found that 45% of studies use incorrect methods for calculating CVA and that practices that render these coefficients meaningless are frequent. This may have important consequences for conclusions drawn from comparative…
A genome-wide association study identifies Arabidopsis thaliana genes that contribute to differences in the outcome of infection with two Turnip mosa…
2021
Viruses lie in a continuum between generalism and specialism depending on their ability to infect more or less hosts. While generalists are able to successfully infect a wide variety of hosts, specialists are limited to one or a few. Even though generalists seem to gain an advantage due to their wide host range, they usually pay a pleiotropic fitness cost within each host. On the contrary, a specialist has maximal fitness within its own host. A relevant yet poorly explored question is whether viruses differ in the way they interact with their hosts’ gene expression depending on their degree of specialization. Using a genome-wide association study approach, we have identified host genes whos…
Copy-number fluctuation by unequal crossing-over in the chicken avidin gene family.
2001
The chicken avidin gene (AVD) forms a closely clustered gene family together with several avidin-related genes (AVRs). In this study, we used fluorescence in situ hybridization on extended DNA fibers (fiber-FISH) to show that the number of the AVD and AVR genes differs between individuals. Furthermore, the gene copy-number showed wide somatic variation in white blood cells of the individuals. The molecular mechanism underlying the fluctuation is most probably unequal crossing-over and/or unequal sister chromatid exchange, as judged by the Gaussian distribution of the gene counts. By definition, an increase in gene number on one locus should be accompanied by a decrease on the other locus in…
Application of whole genome amplification for forensic analysis
2006
Abstract Fundamental to most forensic analyses is the availability of genomic DNA of adequate quality and quantity. To perform a multitude of genetic analyses and assays requires a sufficiently large amount of template. However, DNA yield from forensic samples is frequently limiting the extent of genetic typing. A possible solution to overcome this “bottleneck” of forensic and paleoarcheological DNA analyses could be the amplification of the entire genomic DNA prior to locus specific PCR analysis. Whole Genome Amplification appears to be a promising tool to obtain sufficient DNA amounts from forensic samples of limited quantity.
Development and characterization of 11 microsatellite markers in the rock sparrow, Petronia petronia
2006
Eleven polymorphic microsatellite loci were isolated in the passeriform Petronia petronia using the enrichment protocol FIASCO (fast isolation by AFLP of sequences containing repeats). We detected three to 13 alleles per locus in 25 specimens collected from an Italian population. The level of expected heterozygosity ranged from 0.439 to 0.856. One locus is sex linked to the Z chromosome. The total exclusionary probabilities using these loci for the first and the second parent were 0.978 and 0.999, respectively. These are the first microsatellite loci characterized from the rock sparrow that can be used for estimating population structure and for large-scale parentage analysis.