Search results for "exon"
showing 10 items of 437 documents
Allelic age of the USH2A c.2299delG mutation
2010
24 p., figuras y bibliografía
Polymerase chain reaction analysis of the Xba I polymorphism of the human complement C4 genes provides evidence for strong haplotype conservation.
1995
The genes coding for the two isotypes of the fourth component of human complement, C4A and C4B, are located between the HLA-B and -DR loci of the MHC. We studied the linkage relationship of the previously described XbaI RFLP to obtain further insight into the evolution of the tandemly arranged C4 genes. Using exon-specific PCR amplification followed by restriction analysis and direct DNA sequencing, the polymorphic site could be located in exon 40 of the C4 gene (cDNA position 5095). The polymorphism does not change an amino acid residue. Using nested PCR amplification with isotype-specific primers to amplify either C4A or C4B alleles the haplotype arrangement of the XbaI sites in both isot…
Functional Significance of Microsatellite Markers
2014
The review summarizes literature data on the positive results of association studies between the length of microsatellite repeats and predisposition to pathologies. Actually, the data can be classified according to the localization of the microsatellite: in the gene promoter, in the part of exon 1 coding the signal sequence, in gene introns, in the coding areas of genes, and in 3'-untranslated regions. The functional significance of microsatellite length changes can be evaluated in many cases. The authors came up to the conclusion that further studies on microsatellite associations with diseases remain prospective as they reflect changes in the gene functional activity.
CD45 and multiple sclerosis: the exon 4 C77G polymorphism (additional studies and meta-analysis) and new markers
2003
We re-evaluated the association with multiple sclerosis (MS) of the C77G splicing regulatory variation in the CD45 gene and screened for new mutations the three alternatively spliced exons (#4, 5 and 6). No association with C77G was detected in two groups of patients (total=448) and controls (total=559) from Northern and Southern Italy. When excluding the first published study indicating a positive association, a meta-analysis of the five further studies conducted to date (including the present one) led to a non-significant combined odds ratio (OR) of 1.11. None of the four newly identified nucleotide substitutions, namely C77T (Pro59Pro) in exon 4, G69C (Asp121His) in exon 5, T127A (Ile187…
The copy number variant involving part of the α7 nicotinic receptor gene contains a polymorphic inversion.
2008
The alpha7 nicotinic acetylcholine receptor gene (CHRNA7) is located at 15q13-q14 in a region that is strongly linked to the P50 sensory gating deficit, an endophenotype of schizophrenia and bipolar disorder. Part of the gene is a copy number variant, due to a duplication of exons 5-10 and 3' sequence in CHRFAM7A, which is present in many but not all humans. Maps of this region show that the two genes are in opposite orientation in the individual mainly represented in the public access human DNA sequence database (Build 36), suggesting that an inversion had occurred since the duplication. We have used fluorescent in situ hybridization to investigate this putative inversion. Analysis of inte…
The human fascin gene promoter is highly active in mature dendritic cells due to a stage-specific enhancer.
2003
Abstract Dendritic cells (DC), regarded as the most efficient APCs of the immune system, are capable of activating naive T cells. Thus, DC are primary targets in immunotherapy. However, little is known about gene regulation in DC, and for efficient transcriptional targeting of human DC, a suitable promoter is still missing. Recently, we successfully used the promoter of the murine actin-bundling protein fascin to transcriptionally target DC by DNA vaccination in mice. In this study, we report on isolation of the human fascin promoter and characterization of its regulatory elements. The actively expressed gene was distinguished from a conserved inactive genomic locus and a continuous region …
Homozygous SMN1 exons 1-6 deletion: pitfalls in genetic counseling and general recommendations for spinal muscular atrophy molecular diagnosis.
2012
We report on a rare homozygous intragenic deletion encompassing exons 1-6 of the SMN1 gene in a patient with spinal muscular atrophy (SMA) born into a consanguineous family. This exceptional configuration induced misinterpretation of the molecular defect involved in this patient, who was first reported as having a classic SMN1 exon 7 deletion. This case points out the possible pitfalls in molecular diagnosis of SMA in affected patients and their relatives: exploration of the SMN1 exon 7 (c.840C/T alleles) may be disturbed by several non-pathological or pathological variants around the SMN1 exon 7. In order to accurately describe the molecular defect in an SMA-affected patient, we propose to…
Evaluating the effect of spastin splice mutations by quantitative allele-specific expression assay
2010
Background: Mutations in the SPG4/SPAST gene are the most common cause for hereditary spastic paraplegia (HSP). The splice-site mutations make a significant contribution to HSP and account for 17.4% of all types of mutations and 30.8% of point mutations in the SPAST gene. However, only few studies with limited molecular approach were conducted to investigate and decipher the role of SPAST splice-site mutations in HSP. Methods: A reverse transcriptase-polymerase chain reaction (RT-PCR) analysis and quantitative allele-specific expression assay were performed. Results: We have characterized the consequence of two novel splice-site mutations (c.1493 + 1G>A and c.1414−1G>A) in the SPAST gene…
Genetic characterisation of CSN2 gene in Girgentana goat breed
2014
Among calcium sensitive caseins, β-casein is the most abundant in goat milk, representing up to 50% of total casein content. The goat β-casein locus has been widely investigated and at least ten alleles have been identified in different goat breeds. The aim of this work was to investigate the polymorphisms of β-casein gene in Girgentana dairy goat breed in order to assess the genotype distribution and evaluate how frequencies have changed during the last 10 years, as genotype is known to influence technological and nutritional milk properties. Sequencing analysis and alignment of the obtained sequences of β-casein exon 7, showed the presence of C, C1, and A strong alleles, and 0' null allel…
The human complement component C8B gene: structure and phylogenetic relationship
1993
The eighth component of human complement (C8) is a serum protein that consists of three chains (alpha, beta and gamma), encoded by three separate genes, viz., C8A, C8B, and C8G. In serum, the beta-subunit is non-covalently bound to the disulfide-linked alpha-gamma subunit. Using a full-length C8 beta cDNA probe, we isolated several clones from human genomic lambda DNA libraries. Four lambda clones covering the complete cDNA sequence were characterized by TaqI restriction mapping and were "shotgun" subcloned into M13. C8 beta-cDNA-positive clones were partially sequenced to characterize the 12 exons of the gene with sizes from 69 to 347 bp. All intron-exon junctions followed the GT-AG rule. …