Mayo and colleagues [113] investigated systematically whether flushes were associated with anti-PF4/heparin antibody formation; they found a high frequency of anti-PF4/heparin antibodies by enzyme-linked immunosorbent assay (ELISA), with 1/49 patients testing SRA positive; none developed overt thrombocytopenia, indicating that seroconversion was not associated with formation of aHIT antibodies. This evidence concerns the gene PF4 and Thrombocytopenia.