Sarcoidosis and a MIF gene polymorphism: a case-control study in an Irish Population

¹ The Conway Institute of Biomolecular and Biomedical Research, School of Medicine & Medical Science, University College Dublin, Ireland
² Institute of Genetics, QMC, University of Nottingham, England.

^* To whom correspondence should be addressed. E-mail: seamas.donnelly{at}ucd.ie.

	Abstract

Macrophage Migration Inhibitory Factor is a key pro-inflammatory mediator. A 5-CATT repeat functional polymorphism within the promoter of the gene associated with lowest promoter activity. Our hypothesis is that patients exhibiting a 5-CATT allele would have a less aggressive inflammatory response with an associated less severe clinical phenotype in sarcoidosis.

Irish Caucasian Sarcoidosis patients (n=173) followed up for 1 to 39 years and a control group (n=166) were genotyped for the CATT repeat polymorphism. Disease severity at diagnosis and currently was assessed by the presence of thoracic and extrathoracic symptoms, Erythema Nodosum, radiographic interstitial changes (Chest X-ray score equal to stage II or greater or high resolution computerised tomography confirmed), pulmonary function tests, steroid use, and current erythrocyte sedimentation rate, c-reactive protein and angiotensin converting enzyme levels.

In an Irish population no evidence was found of a significant association between either sarcoidosis susceptibility and disease severity and the 5-CATT repeat functional polymorphism in the Macrophage migration inhibitory gene.

This work found no significant association between the MIF 5-CATT repeat Macrophage Migration Inhibitory Factor gene polymorphism and sarcoidosis and would not support the overriding role for Macrophage Migration Inhibitory Factor in driving sarcoidosis pathogenesis.