However, the alterations in matrix metalloproteinase 12 in RIPK3−/− mice were not substantial, which suggests that MLKL deletion is more effective in preventing emphysema than RIPK3 deletion, possibly because RIPK3 affects apoptotic and necroptotic pathways, whereas MLKL represents a necroptosis-specific effect. The gene discussed is MMP12; the disease is pulmonary emphysema.