NRAMP1 Gene (nramp1 + gene)

Distribution by Scientific Domains


Selected Abstracts


Role of functional polymorphisms of NRAMP1 gene for the development of Crohn's disease

INFLAMMATORY BOWEL DISEASES, Issue 10 2008
Maria Gazouli PhD
Abstract Background: Crohn's disease (CD) is characterized by chronic activation of macrophages. Natural resistance-associated macrophage protein 1 (NRAMP1) gene exerts many pleiotropic effects on macrophage functions. Hence, NRAMP1 may be also involved in the resistance to intracellular pathogens, and this effector of the innate immunity might be involved in CD pathogenesis. Polymorphic alleles at the NRAMP1 locus have been previously associated with susceptibility both to the putative infectious agents and to autoimmune disorders. Based on these indications, in the present study we investigate its candidacy as a genetic determinant for CD in a Greek population in an association-based study, comparing frequencies of 274 CD patients to these of 200 healthy control subjects. Methods: The 5,(GT)n promoter polymorphism and 9 either single nucleotide (SNPs) or insertion/deletion type polymorphisms were genotyped across the NRAMP1 gene. Reverse-transcriptase polymerase chain reaction (RT-PCR) and immunohistochemistry were performed in order to investigate the NRAMP1 mRNA levels in RNA isolated from biopsies of CD patients as well as protein expression in tissues. Results: Three NRAMP1 polymorphisms [5,(GT)n, D543N, and INT4G/C] were significantly associated with CD. Consistent with previous autoimmune disease studies, allele 3 at the functional 5,(GT)n promoter region repeat polymorphism, was significantly associated with CD when compared to healthy controls (odds ratio 1.50; 95% confidence interval [CI]: 1.16,1.95; P = 0.002). Interestingly, we observed that CD patients homozygous for allele 3 expressed higher NRAMP1 mRNA levels compared to carriers of allele 2. Furthermore, the protein levels of allele 3 carriers in tissues were also elevated compared to those of allele 2 carriers. Based on these data we can speculate that overrepresentation of allele 3 in CD patients could lead to hyperactivation of bowel-wall macrophages that are chronically exposed to lipopolysaccharide and this could subsequently cause the autoimmune-like phenotype characteristic of CD. Conclusions: Collectively, our data indicate that genetic polymorphisms of NRAMP1 might be associated with susceptibility to CD. (Inflamm Bowel Dis 2008) [source]


NRAMP1 (SLC11A1) gene polymorphisms that correlate with autoimmune versus infectious disease susceptibility in tuberculosis and rheumatoid arthritis

INTERNATIONAL JOURNAL OF IMMUNOGENETICS, Issue 1 2009
Ö. Ates
Summary NRAMP1 gene has multiple pleiotropic effects on macrophage activation pathways. These pleiotropic effects may increase resistance to infections such as tuberculosis (TB), but may also lead to susceptibility of autoimmune diseases such as rheumatoid arthritis (RA). It has been hypothesized that allele 3 would be associated with autoimmune diseases, whereas allele 2 would be associated with infectious diseases, and genetic factors that enhanced survival in the epidemics of TB might have led to susceptibility for the development of RA. We analysed four NRAMP1 gene polymorphisms including 5, promoter (GT)n (rs34448891), INT4 (469 + 14G/C) (rs3731865), 3,UTR (1729 + 55del4) (rs17235416) and D543N (codon 543, Asp to Asn) (rs17235409) in 112 patients with TB, 98 patients with RA, 80 healthy controls for TB and 122 healthy controls for RA using ARMS-PCR and PCR-RFLP. We found a significant association between INT4 and RA (P = 0.004, odds ratio: 2.06, 95% CI: 1.24,3.41), but no significant differences between 5, promoter, D543N, 3,UTR polymorphisms and RA. There were no associations between NRAMP1 gene polymorphisms and TB. Similarly, no significant differences were observed between NRAMP1 polymorphisms and rheumatoid factor positivity and erosive disease in RA and localization of TB. INT4 polymorphism may be associated with RA in Turkish patients. [source]


Polymorphism in the Rhesus macaque (Macaca mulatta) NRAMP1 gene: lack of an allelic association to tuberculosis susceptibility

JOURNAL OF MEDICAL PRIMATOLOGY, Issue 1 2002
Amos S. Deinard
Although previous tuberculosis (TB) research has suggested that underlying genetic factors influence a host's response and ability to survive Mycobacterium infection, only recently has a gene been identified, the `natural resistance-associated macrophage protein 1' (NRAMP1) gene, which provides a degree of natural resistance to infection by some Mycobacterium species. To date, however, the role that NRAMP1 may play in resistance to Mycobacterium infection has only been examined in mouse and man. Here, we present data generated at NRAMP1 among a group of rhesus macaques (Macaca mulatta) that were euthanized because of an outbreak of Mycobacterium tuberculosis during quarantine. Data were also generated on unrelated (and healthy) rhesus macaques in order to better determine the frequency and degree of genetic polymorphism within Macaca at the NRAMP1 locus. These data represent the first study designed to examine the role that NRAMP1 may play in TB susceptibility among rhesus macaques. [source]


Allelic association between the NRAMP1 gene and susceptibility to tuberculosis in Guinea,Conakry

ANNALS OF HUMAN GENETICS, Issue 6 2000
A. C. L. CERVINO
Forty four families from Guinea,Conakry were analysed to test for association between NRAMP1 (Natural Resistance Associated Macrophage Protein 1) polymorphisms and tuberculosis. Each family included at least one affected sib and one parent. Healthy sibs were also analysed and on average the families included four members. A total of 160 individuals were included in the final dataset. The analysis of association was performed using an extended TDT test, TRANSMIT, to allow for missing information in the parental genotypes. Three polymorphisms in the NRAMP1 gene were typed: a microsatellite (CA) repeat, a 4 bp deletion in the 3, untranslated region and a single nucleotide change in intron 4. The single base change in intron 4 was significantly associated (p= 0.036) with tuberculosis. Our results therefore confirm, using a family-based approach on a newly studied population, the previously reported association between this polymorphism and tuberculosis in a population-based study of West Africans. [source]