Search results for "Haplotypes"

Refined analysis of genetic variability parameters in hepatitis C virus and the ability to predict antiviral treatment response.

2008

Summary.  Hepatitis C virus (HCV) infects approximately 3% of the world population. The chronicity of hepatitis C seems to depend on the level of genetic variability. We have recently (Torres-Puente et al., J Viral Hepat, 2008; 15: 188) reported genetic variability estimates from a large-scale sequence analysis of 67 patients infected with HCV subtypes 1a (23 patients) and 1b (44 patients) and related them to response, or lack of, to alpha-interferon plus ribavirin treatment.. Two HCV genome regions were analysed in samples prior to antiviral therapy, one compressing the three hypervariable regions of the E2 glycoprotein and another one including the interferon sensitive determining region …

Ancient Haplotypes at the 15q24.2 Microdeletion Region Are Linked to Brain Expression of MAN2C1 and Children's Intelligence

2016

The chromosome bands 15q24.1-15q24.3 contain a complex region with numerous segmental duplications that predispose to regional microduplications and microdeletions, both of which have been linked to intellectual disability, speech delay and autistic features. The region may also harbour common inversion polymorphisms whose functional and phenotypic manifestations are unknown. Using single nucleotide polymorphism (SNP) data, we detected four large contiguous haplotype-genotypes at 15q24 with Mendelian inheritance in 2,562 trios, African origin, high population stratification and reduced recombination rates. Although the haplotype-genotypes have been most likely generated by decreased or abse…

Correction: Phylogeny of the Eurasian Wren Nannus troglodytes (Aves: Passeriformes: Troglodytidae) reveals deep and complex diversification patterns …

2020

The Mediterranean Basin represents a Global Biodiversity Hotspot where many organisms show high inter- and intraspecific differentiation. Extant phylogeographic patterns of terrestrial circum-Mediterranean faunas were mainly shaped through Pleistocene range shifts and range fragmentations due to retreat into different glacial refugia. Thus, several extant Mediterranean bird species have diversified by surviving glaciations in different hospitable refugia and subsequently expanded their distribution ranges during the Holocene. Such a scenario was also suggested for the Eurasian Wren (Nannus troglodytes) despite the lack of genetic data for most Mediterranean subspecies. Our phylogenetic mult…

Effects of BRCA2 cis-regulation in normal breast and cancer risk amongst BRCA2 mutation carriers

2012

Introduction: Cis-acting regulatory single nucleotide polymorphisms (SNPs) at specific loci may modulate penetrance of germline mutations at the same loci by introducing different levels of expression of the wild-type allele. We have previously reported that BRCA2 shows differential allelic expression and we hypothesize that the known variable penetrance of BRCA2 mutations might be associated with this mechanism. Methods: We combined haplotype analysis and differential allelic expression of BRCA2 in breast tissue to identify expression haplotypes and candidate cis-regulatory variants. These candidate variants underwent selection based on in silico predictions for regulatory potential and di…

Population structure and mitochondrial DNA gene flow in Old World populations of Drosophila subobscura

1992

An extensive survey of mitochondrial DNA (mtDNA) restriction polymorphism in 156 isofemale lines from 29 different geographic populations of Drosophila subobscura distributed throughout the Old World was carried out. Ten restriction enzymes were used, five of which revealed restriction site polymorphism. Of the 31 restriction sites detected, 13 were found to be polymorphic. Comparisons with the mtDNA map of Drosophila yakuba indicate that the variable sites are mainly concentrated in protein genes, especially those corresponding to the NADH complex. A total of 13 different haplotypes were observed, two of which (haplotypes I and II) are quite frequent and widely distributed throughout the p…

C4 DNA RFLP reference typing report.

1990

One hundred and three individual DNA samples (including 23 families) were studied at the gene level during the reference typing of the fourth component of human complement at the VIth Complement Genetics Workshop in Mainz (1989). All samples were analyzed with the restriction enzyme Taq I and with two DNA probes recognizing the 5' ends of both C4 genes and the two adjacent 21-hydroxylase genes. This RFLP is informative for the number of C4 genes as well as for their respective gene size. We found a high degree of variation regarding the number of C4 genes, i.e. haplotypes with 1-3 structural C4 genes of 16 or 22 kb size. By correlating these haplotypes to the complotypes obtained by protein…

Bgl II restriction fragment length polymorphism of human complement C4A gene coincides with BF*F allele of factor B.

1988

Major histocompatibility complex regulation of the class of the immune response: the H-2d haplotype determines poor interferon-γ response to several …

1990

The lymph node cells of CBA (H-2k), but not BALB/c (H-2d) mice, release interferon (IFN)-gamma into the supernatant when immunized with picryl chloride epicutaneously and then exposed to antigen (haptenized cells) in vitro 4 days later. The failure in IFN-gamma production maps to the major histocompatibility complex (MHC; H-2d) in the congenic BALB/c, BALB/k and BALB/b mice. The evidence that this is an MHC regulation of the class of response to a range of antigens and not a classical Ir gene effect is (a) the difference is seen with several antigens including picryl chloride, "oxazolone" and purified protein derivative of tuberculin and (b) BALB/c mice, which fail to produce IFN-gamma, sho…

Phylogeography and genetic variation of Triatoma dimidiata, the main Chagas disease vector in Central America, and its position within the genus Tria…

2008

Background Among Chagas disease triatomine vectors, the largest genus, Triatoma, includes species of high public health interest. Triatoma dimidiata, the main vector throughout Central America and up to Ecuador, presents extensive phenotypic, genotypic, and behavioral diversity in sylvatic, peridomestic and domestic habitats, and non-domiciliated populations acting as reinfestation sources. DNA sequence analyses, phylogenetic reconstruction methods, and genetic variation approaches are combined to investigate the haplotype profiling, genetic polymorphism, phylogeography, and evolutionary trends of T. dimidiata and its closest relatives within Triatoma. This is the largest interpopulational …

One Species, Hundreds of Subspecies? New Insight into the Intraspecific Classification of the Old World Swallowtail (Papilio machaon Linnaeus , 1758)…

2022

The Old World swallowtail Papilio machaon Linnaeus, 1758 is one of the most well-known and most characteristic members of the family Papilionidae. Over the past two centuries, the butterfly has been the subject of many studies. P. machaon is characterised by a tendency to change the wing colour pattern. In turn, due to the great interest of collectors and amateur entomologists, these studies have been converted into the description of over 100 colour forms, aberrations and subspecies. In this study, mitochondrial DNA (mtDNA), 16S rDNA and cytochrome b sequences were used to examine the correlation between the intraspecific classification and genetic structure of P. machaon. The study used 8…