The 'A2' allele of the platelet specific alloantigen system is encoded by rs5918(C), and it has been implicated as increasing the risk of myocardial infarctions, heart disease, and resistance to blood-thinning benefits of aspirin.
On its own, the A2 allele is implicated especially in early onset heart disease [PMID 8598867]; in combination with the 4G allele of the PAI1 gene, rs1799889, the increased risk of myocardial infarction in a Finnish study population was 4 fold higher (odds ratio = 4.5, p=0.001), particularly in males (odds ratio = 6.4, p=0.0005) [PMID 9700201]. Olympic skater Sergei Grinkov, who had this risk factor, died of a heart attack at age 28. 
A protective effect of rs5918 has also been observed for the development of Non-Hodgkin Lymphoma, both for the SNP (which is also known as L59P) and for its gene, ITGB3. The odds ratio is 0.66 (CI: 0.52-0.85).[PMID 17827388]
[PMID 19876733] rs5918 is not associated with breast cancer risk for either BRCA1 or BRCA2 mutation carriers, based on a multi-center study including ~10,000 patients from 34 studies.
[PMID 19786296] Platelet glycoprotein GP VI 13254C allele is an independent risk factor of premature myocardial infarction
[PMID 20406466] Genetic variants associated with fasting blood lipids in the U.S. population: Third National Health and Nutrition Examination Survey
[PMID 20472470] Impact of COX-2 rs5275 and rs20417 and GPIIIa rs5918 Polymorphisms on 90-Day Ischemic Stroke Functional Outcome: A Novel Finding
[PMID 22133274] Polymorphisms of PAI-1 and platelet GP Ia may associate with impairment of renal function and thrombocytopenia in Puumala hantavirus infection
[PMID 22270286] Preimplantation genetic diagnosis for fetal neonatal alloimmune thrombocytopenia due to antihuman platelet antigen maternal antibodies
|Disease||PL(A1)/(A2) ALLOANTIGEN POLYMORPHISM Thrombocytopenia Posttransfusion purpura Myocardial infarction Fracture|
|CLNDBN||PL(A1)/(A2) ALLOANTIGEN POLYMORPHISM Thrombocytopenia, neonatal alloimmune Posttransfusion purpura Myocardial infarction Fracture, hip, susceptibility to|
|CLNSRC||ClinVar OMIM Allelic Variant|
|CLNACC||RCV000014519.2, RCV000014520.19, RCV000014521.25, RCV000014522.2, RCV000014524.2,|
[PMID 17107626] Comparison of PrASE and Pyrosequencing for SNP Genotyping.
[PMID 17999363] Multifactor dimensionality reduction-phenomics: a novel method to capture genetic heterogeneity with use of phenotypic variables.
[PMID 18035074] Association of polymorphisms in platelet and hemostasis system genes with acute myocardial infarction.
[PMID 18045240] Immunologic and structural analysis of eight novel domain-deletion beta3 integrin peptides designed for detection of HPA-1 antibodies.
[PMID 18513389] New application of intelligent agents in sporadic amyotrophic lateral sclerosis identifies unexpected specific genetic background.
[PMID 18936436] Prevalence in the United States of selected candidate gene variants: Third National Health and Nutrition Examination Survey, 1991-1994.
[PMID 19131662] A meta-analysis of candidate gene polymorphisms and ischemic stroke in 6 study populations: association of lymphotoxin-alpha in nonhypertensive patients.
[PMID 19263529] Genetic risk factors in recurrent venous thromboembolism: A multilocus, population-based, prospective approach.
[PMID 19330901] Association of 77 polymorphisms in 52 candidate genes with blood pressure progression and incident hypertension: the Women's Genome Health Study.
[PMID 19559392] A candidate gene association study of 77 polymorphisms in migraine.
[PMID 20031584] Genetics of atherothrombotic and lacunar stroke.
[PMID 21353223] Association of the platelet GPIIb/IIIa polymorphism with atherosclerotic plaque morphology: the Atherosclerosis Risk in Communities (ARIC) Study.
[PMID 22015659] Mean platelet volume and integrin alleles correlate with levels of integrins alpha(IIb)beta(3) and alpha(2)beta(1) in acute coronary syndrome patients and normal subjects.
|qualified_impact||Insufficiently evaluated not reviewed|
[PMID 24289603] Investigation of ICAM-1 and β3 Integrin Gene Variations in Patients with Brain Tumors
[PMID 23533563] Novel risk factors for premature peripheral arterial occlusive disease in non-diabetic patients: a case-control study.
[PMID 23628433] Genetic association and gene-gene interaction analyses suggest likely involvement of ITGB3 and TPH2 with autism spectrum disorder (ASD) in the Indian population.