Background Genetic and environmental factors are known to play a role in the pathogenesis of spondyloarthropathies (SPA). Mannose binding lectin (MBL) which is a member of collectin family proteins, is an important component of innate immunity. Low levels of MBL is associated with susceptibility to infections. Several variants of MBL gene may result in MBL deficiency. MBL gene polymorphisms and MBL deficiency are shown to be related with several autoimmune and inflammatory diseases.
Objectives The relationship between the MBL levels or MBL gene polymorphisms and SPA predisposition has previously been investigated in a few small studies with conflicting results. In this particular study, we aimed to assess the relationship of the MBL genes in the develepoment of SPA in a group of Turkish patients.
Methods Study included 132 patients with SPA (75 female, 57 male, mean age: 43.0±12.4) and 87 healthy subjects (58 women, 29 men, mean age: 40.3±13.4) as control group. Eighty nine of the SPA patients had ankylosing spondylitis (AS) and 43 had non-AS SPA. MBL gene single nucleotide polymorphisms (SNP) in the codons 52, 54 and 57 of exon 1 were studied by sequencing method.
Results G54D G>A polymorphism was not different between the patient and the healthy control groups (p=0.291). The frequencies of R52C C>T and G57E G>A polymorphisms were found to be significantly higher in the SPA patients than those of the healthy controls (p=0.019 and 0.001 respectively). While the non-AS subgroup showed significancy for both R52C C>T and G57E G>A polymorphisms (p=0.004 and 0.000 respectively), the AS subgroup showed significancy only for G57E G>A (p=0.113 and 0.014 respectively). Clinical characteristics of either AS or non-AS SPA patients were not associated with any of the MBL polymorphisms. In a previous study, haplotypes of MBL genetic polymorphisms were found to be associated with AS in Korean patients. Our study is the first one from Turkey indicating the relationship between SPA's and MBL gene polymorphisms.
Conclusions Even though we had rather small sample size, our results showed significantly higher R52C C>T and G57E G>A polymorphisms in Turkish patients with SPA. Therefore we may suggest that MBL gene polymorphisms could be related with the predisposition of the disease.
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Disclosure of Interest None declared