The c.605T>G variant in ITGA2B is a missense variant predicted to cause substitution of phenylalanine by cystine at amino acid 202. At least one patient (Proband in PMID:15219201) with this variant displayed mucocutaneous bleeding and impaired aggregation with all agonists except ristocetin, which is highly specific for Glanzmann thrombasthenia (PP4_moderate). The variant has been reported to segregate with Glanzmann thrombasthenia in the proband (confirmed by bleeding phenotype and platelet aggregometry) plus two affected family members, all with the homozygous genotype with the c.605T>G variant. (PP1_moderate; PMID:15219201). This variant is absent from gnomAD v2.1.1 (PM2_Supporting). Surface expression of αIIbβ3 measured by flow cytometry in CHO cells transiently co-transfected with p.Phe202Cys αIIb and wild type β3 showed absent expression (<5%) WT levels, indicating that this variant impacts protein function (PMID:15219201)(PS3). The computational predictor REVEL gives a score of 0.781, which is above the ClinGen PD VCEP threshold of >0.7 and predicts a damaging effect on function (PP3). In summary, this variant meets the criteria to be classified as Pathogenic for autosomal recessive Glanzmann Thrombasthenia based on the ACMG/AMP criteria applied, as specified by the ClinGen PD VCEP: PS3, PP1_moderate, PP4_moderate, PP3, PM2_supporting. (VCEP specifications version 2; date of approval 03/07/2024)