NAT2*73 is assigned decreased function based on moderate evidence. NAT2*73 is defined by the core SNVs c.341T>C (p.I114T) and c.802A>G (p.R268G). c.341T>C (p.I114T) defines NAT2*5 which has been extensively studied, exhibiting decreased N-acetyltransferase activity both in vivo and in vitro. In vitro studies also show that NAT2*5 (which contains the core SNV c.341T>C, p.I114T) is subjected to enhanced protein degradation by the proteasome (15564878). Thus, NAT2*73 would presumably be degraded in the same manner. Additionally, five out of ten variant effect predictors tested by CPIC staff predict that c.341T>C (p.I114T) impairs protein function. There is no literature describing function for c.802A>G. Three out of eight variant effect predictors tested by CPIC staff predict that c.802A>G (p.R268G) impairs protein function. NAT2*73 is assigned decreased function based on c.341T>C. Despite this, the combinatorial effects associated with c.341T>C and c.802A>G are uncertain.