Cytotoxic T lymphocyte antigen–4 gene polymorphisms do not confer susceptibility to autoimmune hepatitis types 1 and 2 in Brazil

• Published in: The American journal of gastroenterology Vol. 98; no. 7; pp. 1616 - 1620
• Main Authors: Bittencourt, Paulo L, Palácios, Selma A, Cançado, Eduardo L.R, Porta, Gilda, Carrilho, Flair J, Laudanna, Antonio A, Kalil, Jorge, Goldberg, Anna C
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Inc 01.07.2003; Blackwell Publishing
• Subjects: Adolescent; Adult; Aged; Antigens, CD; Antigens, Differentiation - genetics; Biological and medical sciences; Brazil; Case-Control Studies; Child; Child, Preschool; CTLA-4 Antigen; Female; Gastroenterology. Liver. Pancreas. Abdomen; Gene Frequency; Genetic Predisposition to Disease; Genotype; Hepatitis, Autoimmune - classification; Hepatitis, Autoimmune - genetics; Humans; Infant; Liver. Biliary tract. Portal circulation. Exocrine pancreas; Male; Medical sciences; Middle Aged; Other diseases. Semiology; Polymerase Chain Reaction; Polymorphism, Genetic; Tropical medicine; South America; Brazil; America; Human; Immunopathology; Hepatic disease; Autoimmune disease; Genetic determinism; Statistical study; Antigen; Hepatitis; Predisposition; Digestive diseases; Genetics; Cytotoxic T lymphocyte; Polymorphism
• ISSN: 0002-9270; 1572-0241
• DOI: 10.1016/S0002-9270(03)00307-1

Susceptibility to autoimmune hepatitis (AIH) has been linked to different HLA-DR antigens in distinct populations. Recently, an A–G polymorphism in exon 1 of the cytotoxic T lymphocyte antigen-4 (CTLA-4) gene was associated with predisposition to AIH type 1 (AIH-1) in white individuals in North America. This polymorphism has been associated with several other autoimmune diseases, presumably because of its effect in the expression of CTLA-4, an adhesion molecule that downregulates peripheral T cell responses. The aims of this study were to assess the frequency of CTLA-4 genotypes in Brazilian patients with AIH-1 and AIH type 2 (AIH-1), as well as to investigate the influence of these genotypes in disease expression. Determination of CTLA-4 genotypes was carried out in 106 patients with AIH-1, 26 subjects with AIH-2, and 67 healthy control subjects by polymerase chain reaction (PCR)–based techniques. No difference in the distribution of CTLA-4 genotypes was observed in subjects with AIH-1 and AIH-2 as compared to healthy controls. Patients with AIH-1 and AIH-2 with the GG genotype exhibited lower γ-globulin and ALT levels, respectively. Susceptibility to AIH-1 and AIH-2 in Brazilian patients is not influenced by exon 1 CTLA-4 gene polymorphisms at position 49.