July - September 2011, Volume 7, Issue 3

Duncea I, Crisan L, Ilie L, Paul A, Popp R

Cytotoxic t-lymphocyte Antigen 4 (ctla-4) - 1661 a/g and -658 c/t Gene Polymorphisms in Autoimmune Thyroid Diseases: a Pilot Study

Acta Endo (Buc) 2011, 7 (3): 413-423
doi: 10.4183/aeb.2011.413

Introduction. Autoimmunity derives from a complex interplay of genetic and environmental factors. Major histocompatibility complex (MHC) alleles and non-MHC loci have been identified as susceptibility markers. Few studies evidenced an association between autoimmune thyroid disease (ATD) and CT60 or 49 A/G polymorphisms in the CTLA-4 gene. Objectives. The aim of our research was to investigate in a pilot case-control study whether other two CTLA-4 gene polymorphisms, i.e. the CTLA-4 1661 A/G and the CTLA-4 658 C/T single nucleotide polymorphisms (SNP), are involved in genetic predisposition to ATD. Material and methods. Between January and April 2009, 42 subjects entered the study. Of these, ATD (i.e. chronic autoimmune thyroiditis, Graves’ disease) was diagnosed in 21 patients, whereas in 21 subjects no signs of autoimmunity were identified. CTLA-4 gene polymorphisms were genotyped using polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP). Results. No association was observed between the CTLA-4 1661A/G gene polymorphism in patients with ATD and controls (p = 0.094, by chi-square test). Likewise, no statistically significant difference was noticed between groups with regard to the CTLA-4 658 C/T gene polymorphism (p = 0.649). Conclusions. At the time being, this is the first case-control study that examined and demonstrated lack of association between CTLA-4 -1661 A\G and -658 C\T SNP and ATD; however, larger numbers of subjects are needed to clarify the role of CTLA-4 gene polymorphisms in endocrine autoimmunity.

Keywords: autoimmune thyroid disease, Graves' orbitopathy, cytotoxic Tlymphocyte antigen-4, single nucleotide polymorphism.

Correspondence: I. Duncea MD, PhD, University of Medicine and Pharmacy Cluj-Napoca, - Endocrinology Department, 3 Louis Pasteur Cluj-Napoca 400349, Romania, Tel: +40264439258 Fax: +40264439258 email: ileanaduncea@yahoo.com