Familial associations of rheumatoid arthritis with autoimmune diseases and related conditions
OBJECTIVE: In the era of genome-wide association studies, familial risks are used to estimate disease heritability and the likelihood of candidate-gene identification. This study was undertaken to estimate associations of rheumatoid arthritis (RA) with any of 33 autoimmune diseases and related conditions among parents and offspring, singleton siblings, twins, and spouses.METHODS: The Multigenerati
