Association between EcoRI fragment-length polymorphism of the immunoglobulin lambda variable 8 (IGLV8) gene family with rheumatoid arthritis and systemic lupus erythematosus

Author(s)

R.G.P. Queiroz ^[1] ; M.C. Tamia-Ferreira ^[2] ; I.F. Carvalho ^[3] ; F.C. Petean ^[4] ; G.A.S. Passos

Affiliation

^[1] Universidade de São Paulo. Departamento de Genética. Grupo de Imunogenética Molecular (GIM)

^[2] Universidade de São Paulo. Departamento de Genética. Grupo de Imunogenética Molecular (GIM)

^[3] Universidade de São Paulo. Faculdade de Medicina de Ribeirão Preto. Departamento de Clínica Médica

^[4] Universidade de São Paulo. Faculdade de Medicina de Ribeirão Preto. Departamento de Clínica Médica

• Document type: Journal article
• Source: Brazilian Journal of Medical and Biological Research; v. 34, n. 4, p. 525-528, 2001-04-00.

Abstract

The human immunoglobulin lambda variable 8 (IGLV8) subgroup is a gene family containing three members, one of them included in a monomorphic 3.7-kb EcoRI genomic fragment located at the major lambda variable locus on chromosome 22q11.1 (gene IGLV8a, EMBL accession No. Z73650) at 100% frequency in the normal urban population. The second is a polymorphic RFLP allele included in a 6.0-kb EcoRI fragment at 10% frequency, and the third is located in a monomorphic 8.0-kb EcoRI fragment at 100% frequency, the last being translocated to chromosome 8q11.2 and considered to be an orphan gene. Our Southern blot-EcoRI-RFLP studies in normal individuals and in patients with rheumatoid arthritis (RA) or with systemic lupus erythematosus (SLE), using a specific probe for the IGLV8 gene family (probe pVL8, EMBL accession No. X75424), have revealed the two monomorphic genomic fragments containing the IGLV8 genes, i.e., the 3.7-kb fragment from chromosome 22q11.1 and the 8.0-kb fragment from 8q11.2, both occurring at 100% frequency (103 normal individuals, 48 RA and 28 SLE patients analyzed), but absence of the 6.0-kb IGLV8 polymorphic RFLP allele in all RA or SLE patients. As expected, the frequency of the 6.0-kb allele among the normal individuals was 10%. These findings suggest an association between the absence of the 6.0-kb EcoRI fragment and rheumatoid arthritis and systemic lupus erythematosus. (AU)