A highly informative microsatellite marker, D7S485, from the T-cell receptor gamma (TCRG) locus, has been used to study segregation of TCRG genes in 26 multiplex rheumatoid arthritis (RA) families. We used the sib-pair method to assess excess identity-by-descent sharing among affected members in these families and the LINKAGE package of programs was used to calculate two-point lod scores for the D7S485 marker. There was no evidence for segregation of TCRG genes with RA in affected siblings and significantly negative lod scores were obtained from linkage analyses using both autosomal dominant and recessive models of inheritance.