Authors: Alexandra Zhernakova Peter Eerligh Pilar Barrera Joanna Z Weseloy Tom W J Huizinga Bart O Roep Cisca Wijmenga Bobby P C Koeleman
Publish Date: 2005/07/16
Volume: 118, Issue: 1, Pages: 58-66
Abstract
Cytotoxic T lymphocyteassociated antigen 4 CTLA4 is an important negative regulator of Tcell response and its genetic association with type 1 diabetes T1D has recently been demonstrated The frequent coassociation of autoimmune diseases AID and the implication from multiple genome scans that the CTLA4 gene region is a general autoimmune region led us to study the role of CTLA4 in independent cohorts of T1D coeliac disease CD and rheumatoid arthritis RA patients We present independent data that confirm the association of CTLA4 in Dutch patients with juvenile onset T1D and show differential association of CTLA4 with CD and RA The CTLA4 gene polymorphisms were tested for association in 350 T1D 310 CD 520 RA patients and 900 controls In addition 218 families were tested by the transmission disequilibrium test TDT T1D patients showed the highest association with the MH30G −1147C +49G CT60G JO37 3G haplotype 2 in both a case/control cohort P=0002 OR=142 and by TDT P=002 OR=143 In contrast this haplotype showed no association in the RA and CD cohorts However we observed an increased frequency of the MH30G −1147T +49A CT60G JO37 3A haplotype 3 in the CD patients diagnosed at a young age OR=16 P=0026 P c=0052 Furthermore when T1D and CD patients were stratified based on the HLA risk the T1D susceptible CTLA4 haplotype 2 was overrepresented in the high HLArisk T1D and CD groups In conclusion we confirmed association between CTLA4 haplotype 2 and T1D in the Dutch population Association with another CTLA4 haplotype haplotype 3 was confirmed for CD but only in those patients who had an early age of expression No effect was found between RA and CTLA4 The association of the CTLA4 haplotype 2 with the highrisk HLA genotype in T1D and CD which share DQ2 as the one of highrisk alleles might provide a clue to understanding the common genetic background of AIDWe wish to thank all the patients and their families who participated in the study We thank Alfons Bardoel for help with genotyping Harry van Someren for his work on the patient database Alienke Monsuur and Peter Eerligh for useful discussions and Jackie Senior for editing the manuscript This study was supported by grants from the Dutch Diabetes Research Foundation 97137 the Dutch Digestive Diseases Foundation WS 03–06 the Netherlands Organisation for Health Research and Development ZonMW 91202028 the Juvenile Diabetes Research Foundation International JDRF 200110004 and the Coeliac Disease Consortium an Innovative Cluster approved by the Netherlands Genomics Initiative and partly funded by the Dutch Government BSIK03009
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