The severe form of macro‐thrombocytopenia in an infant (Patient 13; Table 2; Fig 1G,H; Table S3), was the consequence of a heterozygous mutation in the gene encoding the myosin heavy chain 9 (MYH9, p.S96L), while a novel heterozygous p.G165R mutation in the RUNX1 gene, which encodes the haematopoietic runt related transcription factor 1, was responsible for a mild form of chronic normocytic thrombocytopenia in an eight‐year‐old girl (Patient 12; Table 2; Table S3) (Sood et al, 2017). Here, RUNX1 is linked to Thrombocytopenia.