Thrombocytopenia 6

A syndromic constitutional thrombocytopenia caused by a variation in the SRC gene, characterized by congenital thrombocytopenia, small platelets, and an increased bleeding tendency beginning in infancy or childhood. Affected individuals show impaired megakaryocyte maturation, reduced proplatelet formation, and altered cytoskeletal organization in patient-derived megakaryocytes, consistent with dysregulated SRC kinase signaling. Platelet function studies show variable but generally mild platelet defects, with bleeding phenotypes ranging from easy bruising to mucocutaneous bleeding.