Lack of linkage between anti-nuclear antibody or clinical features of systemic lupus erythematosus (SLE) and TCR-A/Vbeta loci in families of subjects with SLE.

The role of the TCR-A and TCR-Vbeta genes in the genetic predisposition to SLE expression and anti-nuclear antibody (ANA) production were examined by linkage analysis in eighteen multiplex and forty-three simplex SLE families. All subjects were Caucasian. A significantly increased prevalence of positive ANAs in first-degree relatives of SLE patients from multiplex families was noticed compared to that of simplex families. Linkage between TCR-A/Vbeta genes and SLE expression and ANA production were analysed by affected sib-pair method. Results showed that the haplotypes identical by descent sharing TCR-A and TCR-Vbeta genes in the affected sib-pairs was not different from that expected (P = 0.93 and P = 0.74, respectively). There was no linkage between ANA positivity and TCR-A and TCR-Vbeta genes in ANA positive sib-pairs from both multiplex and simplex families. This study suggests that germline TCR-A and TCR-Vbeta gene loci confer no susceptibility to ANA and SLE expression.