Least One Copy (least + one_copy)

Distribution by Scientific Domains


Selected Abstracts


Quantification of SMN1 and SMN2 genes by capillary electrophoresis for diagnosis of spinal muscular atrophy

ELECTROPHORESIS, Issue 13 2008
Chun-Chi Wang
Abstract We present the first CE method for the separation and quantification of SMN1 and SMN2 genes. Spinal muscular atrophy (SMA) is an inherited neuromuscular disorder deleted or mutated in SMN1 gene and retained at least one copy of SMN2 gene. However, these two genes are highly homologous, differentiation and quantification of SMN1 and SMN2 are therefore required in diagnosis to identify SMA patients and carriers. We developed a fluorescence-labeled conformation-sensitive CE method to quantitatively analyze PCR products covering the variable position in the SMN1/SMN2 genes using a copolymer solution composed of hydroxyethylcellulose and hydroxypropylcellulose. The DNA samples included 24 SMA patients, 52 parents of SMA patients (obligatory carriers), and 255 controls. Those 331 samples were blind analyzed to evaluate the method, and the results compared with those obtained using denaturing HPLC (DHPLC). Validation of accuracy was performed by comparing the results with those of DHPLC. Nine of total samples showed different results. Diagnosis of one fetus DNA among them was related to abortion or not, which was further confirmed by gel electrophoresis and DNA sequencing. Our method showed good coincidence with them, and proved the misdiagnosis of DHPLC. This simple and reliable CE method is a powerful tool for clinical genotyping of large populations to detect carriers and SMA patients. [source]


APOE epsilon-4 allele and cytokine production in Alzheimer's disease

INTERNATIONAL JOURNAL OF GERIATRIC PSYCHIATRY, Issue 4 2010
Paolo Olgiati
Abstract Objective The APOE epsilon-4 allele has consistently emerged as a susceptibility factor for Alzheimer's disease (AD). Pro-inflammatory cytokines are detectable at abnormal levels in AD, and are thought to play a pathophysiological role. Animal studies have shown dose-dependent correlations between the number of APOE epsilon-4 alleles and the levels of pro-inflammatory cytokines. The aims of this study were to investigate the influence of APOE genotypes on TNF- ,, IL-6, and IL-1, secreted by peripheral blood mononuclear cells (PBMC) from human patients with AD and to analyze the correlation between cytokine production and AD clinical features. Methods Outpatients with AD (n,=,40) were clinically evaluated for cognitive decline (MMSE) and psychiatric symptoms (Cornell Scale for Depression in Dementia; Neuropsychiatric Inventory) and genotyped for APOE variants. PBMCs were isolated from the donors and used to assess spontaneous and PMA-stimulated secretion of TNF- ,, IL-6, and IL-1,. Cytokine production was determined by immuno-enzymatic assays (ELISA). Results In comparison with their counterparts without APOE4, patients with at least one copy of the APOE epsilon-4 allele showed higher spontaneous (p,=,0.037) and PMA-induced (p,=,0.039) production of IL-1, after controlling for clinical variables. Significant correlations were reported between NPI scores (psychotic symptoms) and IL-6 production. Conclusion These preliminary findings suggest the involvement of inflammatory response in the pathogenic effect of the APOE epsilon-4 allele in AD, although their replication in larger samples is mandatory. The modest correlations between pro-inflammatory cytokines released at peripheral level and AD features emphasizes the need for further research to elucidate the role of neuroinflammation in pathophysiology of AD. Copyright © 2009 John Wiley & Sons, Ltd. [source]


Initial Evidence of an Association Between OPRM1 and Adolescent Alcohol Misuse

ALCOHOLISM, Issue 1 2010
Robert Miranda
Background:, Considerable research efforts have attempted to identify genes associated with alcoholism among adults, yet few studies have examined adolescents. Identifying genes associated with alcohol misuse in youth is important given that the relative contribution of genetic and environmental influences on alcoholism varies across development. The purpose of this study was to examine the association between a polymorphism of the ,-opioid receptor gene (OPRM1) and alcohol misuse in a sample of youth and to test whether heightened sensitivity to the reinforcing effects of alcohol mediated this relationship. Methods:, Adolescents (n = 187; mean age = 15.4 years; 47.6% female) were genotyped for A118G (rs1799971), a single-nucleotide polymorphism (SNP) of the OPRM1 gene, and assessed for alcohol use disorder (AUD) diagnoses and other psychopathology. Alcohol misuse was also measured continuously to maximize detection of drinking problems in youth. Drinking motives were used to capture the extent to which youth consumed alcohol to enhance positive affect. Results:, AUD groups differed significantly in terms of allelic distributions of the A118G SNP, such that 51.9% of youth with an AUD carried at least one copy of the G allele compared to 16.3% of non-AUD controls. Those who carried the G allele endorsed drinking to enhance positive affect more strongly than those who were homozygous for the A allele and drinking to enhance positive affect mediated the association between OPRM1 and alcohol-related problems. Conclusions:, These data build on findings from adult studies and provide the first evidence that a polymorphism of the OPRM1 receptor gene is associated with the development of early-onset alcohol-related problems during adolescence, in part, by heightening sensitivity to the reinforcing effects of alcohol. [source]


Molecular characterization of swine leucocyte antigen class II genes in outbred pig populations

ANIMAL GENETICS, Issue 4 2010
C.-S. Ho
Summary The highly polymorphic swine leucocyte antigen (SLA) genes are among the most important determinants of swine immune responses to disease and vaccines. Accurate and effective SLA genotyping methods are required to understand how SLA gene polymorphisms affect immunity, especially in outbred pigs with diverse genetic backgrounds. In this study, we present a simple and rapid molecular-based typing system for characterizing SLA class II alleles of the DRB1, DQB1 and DQA loci. This system utilizes a set of 47 sequence-specific PCR primers developed to differentiate alleles by groups that share similar sequence motifs. We applied this typing method to investigate the SLA class II diversity in four populations of outbred pigs (n = 206) and characterized a total of 19 SLA class II haplotypes, six of which were shared by at least three of the sampled pig populations. We found that Lr-0.1 (DRB1*01XX,DQB1*01XX,DQA*01XX) was the most prevalent haplotype with a combined frequency of 16.0%, followed by Lr-0.2 (DRB1*02XX,DQB1*02XX,DQA*02XX) with 14.6% and Lr-0.15b (DRB1*04XX,DQB1*0202,DQA*02XX) with 14.1%. Over 70% of the pigs (n = 147) had at least one copy of one of these three haplotypes. The PCR-based typing system described in this study demonstrates a reliable and unambiguous detection method for SLA class II alleles. It will be a valuable tool for studying the influence of SLA diversity on various immunological, pathological and physiological traits in outbred pigs. [source]


5-(N -ethyl-N-isopropyl)-amiloride enhances SMN2 exon 7 inclusion and protein expression in spinal muscular atrophy cells

ANNALS OF NEUROLOGY, Issue 1 2008
Chung-Yee Yuo PhD
Objective Spinal muscular atrophy (SMA) is a common inherited neuromuscular disorder caused by homozygous loss of function of the survival motor neuron 1 (SMN1) gene. All SMA patients carry at least one copy of a nearly identical SMN2 gene. However, a critical nucleotide change in SMN2 results in alternative splicing and exclusion of exon 7 in the majority of SMN2 messenger RNA (mRNA), thus producing a low level of functional SMN protein. Increasing SMN protein production by promoting SMN2 exon 7 inclusion could be a therapeutic approach for SMA. It has been shown that cellular pH microenvironment can modulate pre-mRNA alternative splicing in vivo. In this study, we tested whether inhibitors of the Na+/H+ exchanger can modulate the exon 7 splicing of SMN2 mRNA Methods We treated SMA lymphoid cell lines with Na+/H+ exchanger inhibitors and then measured SMN2 exon 7 splicing by reverse transcriptase polymerase chain reaction and SMN protein production by Western blotting and immunofluorescence Results We found that treatment with an Na+/H+ exchanger inhibitor, 5-(N -ethyl-N-isopropyl)-amiloride (EIPA), significantly enhances SMN2 exon 7 inclusion and SMN protein production in SMA cells. In addition, EIPA increases the number of nuclear gems in SMA cells. We further explored the underlying mechanism, and our results suggest that EIPA may promote SMN2 exon 7 inclusion through upregulation of the splicing factor SRp20 in the nucleus Interpretation Our finding that EIPA, an inhibitor of the Na+/H+ exchanger, can increase SMN protein expression in SMA cells provides a new direction for the development of drugs for SMA treatment. However, further translational studies are needed to determine whether this finding is applicable for SMA treatment or just a proof of cellular pH effect on SMN splicing. Ann Neurol 2007 [source]


Porphyria cutanea tarda in south-east New South Wales

AUSTRALASIAN JOURNAL OF DERMATOLOGY, Issue 4 2002
Ian McCrossin
SUMMARY Thirteen patients with porphyria cutanea tarda diagnosed between 1994 and 2000 were reviewed to evaluate the precipitating factors and associations of porphyria cutanea tarda in a regional area of coastal and rural NSW. The majority had more than one precipitating factor, with excess alcohol intake, mutations in the haemochromatosis gene, chronic hepatitis C infection and oestrogen therapy being the most common. Antibodies to the hepatitis C virus were detected in 25% and these patients presented at a younger age. Of the patients tested for the two known haemochromatosis gene mutations, six (46%) had at least one copy of the C282Y mutation. Two (15%) patients were homozygous for the C282Y mutation and two (15%) were compound heterozygous for the C282Y and H63D mutations. All patients responded to venesection, which is the treatment of choice for the majority of patients with porphyria cutanea tarda. [source]


The MTHFR 677C,T polymorphism and behaviors in children with autism: exploratory genotype,phenotype correlations

AUTISM RESEARCH, Issue 2 2009
Robin P. Goin-Kochel
Abstract New evidence suggests that autism may be associated with (a) varied behavioral responses to folate therapy and (b) metabolic anomalies, including those in folate metabolism, that contribute to hypomethylation of DNA. We hypothesized that children with autism who are homozygous for the MTHFR 677 T allele (TT) and, to a lesser extent those with the CT variant, would exhibit more behavioral problems and/or more severe problematic behaviors than homozygous wild-type (CC) individuals because of difficulties in effectively converting 5,10-MTHF to 5-MTHF. Data from the Autism Genetic Resource Exchange (AGRE) collection were analyzed for all children who met strict criteria for autism per the Autism Diagnostic Interview,Revised (ADI-R) and the Autism Diagnostic Observation Schedule (ADOS) and who had been genotyped for the 677 C to T MTHFR polymorphism (n=147). Chi-square tests, logistic regression, and one-way ANOVAs were used to determine whether differences existed among MTHFR genotypes for specific behaviors on the ADI-R and indices for level of functioning. Exploratory results indicated four behaviors from the ADI-R that were more common and problematic (95% CI) among those with at least one copy of the T allele as compared to homozygous wild-type individuals: direct gaze, current complex body movements, a history of self-injurious behavior, and current overactivity (ORs=2.72, 2.33, 2.12, 2.47, respectively). No differences existed among genotypes for level of functioning as measured with the Peabody Picture Vocabulary Test,Third Edition, Ravens Colored Progressive Matrices, or the Vineland Adaptive Behavior Scales. Findings call for further investigation of the relationship between folate metabolism and problem behaviors among children with autism. [source]