Abstract
TNF receptor-associated syndrome (TRAPS) is a dominantly inherited autoinflammatory condition caused by mutations in the TNFRSF1A gene. The mechanism underlying the variable expressivity of the common variant R92Q (rs4149584; c.362G>A; p.Arg121Gln) is unclear and is of critical importance for patient care and genetic counseling. This study evaluated the impact of the number of R92Q mutations in two unique unrelated families.