2016) and it has been suggested before that iron deficiency may contribute to the Chuvash pulmonary vascular phenotype (Sable et al. 2012). In this context, Figure 2 shows the striking similarity between the pulmonary vascular response to hypoxia in the current PHD2‐deficient patient and the corresponding response in healthy individuals exposed either to 8 h of hypoxia, or to an 8‐h infusion of the iron chelator desferrioxamine (Smith et al. 2008a). Here, EGLN1 is linked to Iron deficiency anemia.