[Nijmegen Breakage syndrome].

Debreceni Egyetem, Orvos- és Egészségtudományi Centrum Infektológiai és Gyermekimmunológiai Tanszék, Debrecen.
Orvosi Hetilap 04/2010; 151(16):665-73. DOI: 10.1556/OH.2010.28851
Source: PubMed

ABSTRACT Nijmegen Breakage syndrome is a rare, autosomal recessive disorder characterized by severe, combined immunodeficiency, recurrent sinopulmonary infections, chromosomal instability, radiosensitivity, predisposition to malignancy, a "bird-like" facial appearance, progressive microcephaly, short stature, and mental retardation. The syndrome is caused by mutations in the NBS1 gene, which encodes a DNA-repair protein, named nibrin. The authors summarize current knowledge on molecular genetics, diagnostic characteristics and therapeutic options of this inborn error of innate immunity.

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    ABSTRACT: Many studies were published to evaluate the association between Nijmegen breakage syndrome 1 (NBS1) 657del5 polymorphism and breast cancer risk, but the results remained inconsistent. To derive a more precise estimation on the possible association, we performed a meta-analysis of previous published studies. Case-control studies on the association between NBS1 657del5 polymorphisms and breast cancer risk were included into this meta-analysis. We used the odds ratio (OR) with 95 % confidence interval (95 % CI) to assess the strength of the association. Ten studies with a total of 25,365 subjects were identified and included into this meta-analysis. Meta-analysis of those ten studies showed that there was a significant association between NBS1 657del5 polymorphisms and breast cancer risk (pooled OR = 2.66, 95 % CI 1.82-3.90, P < 0.001). The cumulative meta-analyses showed a trend of a more significant association between NBS1 657del5 polymorphisms and breast cancer risk as data accumulated by publication year. Thus, our meta-analysis suggests that there was a significant association between NBS1 657del5 polymorphisms and breast cancer risk, and NBS1 657del5 polymorphism results in an increased risk of breast cancer.
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