The small number of events additionally limits our ability to assess whether the strongest association is between MSA and pSS itself or between MSA and other pSS-associated factors, such as anti-Ro/SSA antibodies; it also limits our ability to assess whether MSA is associated specifically with pSS or with any Sjögren’s syndrome (primary or secondary), although our data strongly suggest the former. The gene discussed is TRIM21; the disease is multiple system atrophy.