Due to the hypothesis that AS was the cause of recurrent anemia, a hematologist was consulted with a recommendation to examine the vWF levels and platelet function testing.[3] The vWF antigen levels were normal, but the analysis of platelet functions (their adhesion and aggregation) using a membrane with collagen/adrenaline and collagen/adenosine diphosphate (platelet function analyzer with collagen/epinephrine and collagen/adenosine diphosphate/ADP/membrane – PFA-COL/EPI and PFA-COL/ADP) indicated a defect in platelet functions. This evidence concerns the gene VWF and anemia (phenotype).