Two new monogenic syndromes of inflammatory arthritis were discovered using whole exome sequencing: the coatomer subunit alpha syndrome because of rare mutations in coatomer subunit alpha and haploinsufficiency of A20 resulting from rare mutations in TNFAIP3.
COPA (coatomer subunit α) syndrome is a newly recognised cause of interstitial lung disease in children and adults, frequently associated with arthritis and renal dysfunction.