has characteristic has characteristic has material basis in germline mutation in ITGA2B Autosomal recessive inheritance autosomal recessive disease Glanzmann thrombasthenia 1 https://github.com/monarch-initiative/mondo/issues/10711 https://github.com/monarch-initiative/mondo/issues/9994 https://www.malacards.org/card/glanzmann_thrombasthenia_1 Platelet glycoprotein 2B 3A deficiency DOID:2219 MONDO:0031332 BDPLT2 OMIM:273800 Glanzmann thrombasthenia type A deficiency of GP 2B 3A complex thrombasthenia A platelet type bleeding disorder characterized by lifelong mucocutaneous bleeding, markedly impaired platelet aggregation, and absent or severely reduced clot retraction due to failure of the αIIbβ3 integrin complex to bind fibrinogen. Platelets appear normal in number and morphology, but aggregation responses to physiologic agonists (including ADP, collagen, epinephrine, and thrombin) are severely decreased or absent, while ristocetin‑induced agglutination remains normal. Biallelic loss‑of‑function ITGA2B variants reduce or abolish surface expression of the αIIbβ3 receptor, preventing fibrinogen‑mediated platelet bridging and producing the classic Glanzmann thrombasthenia phenotype. ITGA2B-related Glanzmann thrombasthenia SCTID:32942005 Glanzmann's thrombasthenia MESH:D013915 Diacyclothrombopathia 2B 3A thrombasthenia of Glanzmann and Naegeli GARD:0015240 platelet glycoprotein IIb-IIIa deficiency NCIT:C61249 GT bleeding disorder, platelet-type, 2 Glanzmann thrombasthenia