In this cohort, we found no difference in residual ADA2 enzyme activity in hematologic patients compared to vasculopathy patients, contrary to what has been previously described by Lee et al. On the other hand, using an in vitro overexpression system with 20-fold higher ADA2-activity than in vivo, Lee et al. predicted that the differences in residual activity they found in vitro will not be observable in vivo [6]. This evidence concerns the gene ADA2 and vascular disorder.