{{Rsnum
|rsid=3181096
|Gene=CD28
|Chromosome=2
|position=203705369
|Orientation=plus
|GMAF=0.3228
|Gene_s=CD28
|Assembly=GRCh38
|GenomeBuild=38.1
|dbSNPBuild=141
|geno1=(C;C)
|geno2=(C;T)
|geno3=(T;T)
}}{{ population diversity
| geno1=(C;C)
| geno2=(C;T)
| geno3=(T;T)
| CEU | 34.5 | 54.0 | 11.5
| HCB | 56.9 | 41.6 | 1.5
| JPT | 38.1 | 53.1 | 8.8
| YRI | 49.7 | 43.5 | 6.8
| ASW | 45.6 | 40.4 | 14.0
| CHB | 56.9 | 41.6 | 1.5
| CHD | 47.7 | 45.9 | 6.4
| GIH | 14.9 | 39.6 | 45.5
| LWK | 64.5 | 29.1 | 6.4
| MEX | 46.6 | 39.7 | 13.8
| MKK | 66.7 | 30.1 | 3.2
| TSI | 36.3 | 48.0 | 15.7
| HapMapRevision=28
}}{{PMID Auto
|PMID=24103478
|Title=Contribution of PTPN22, CD28, CTLA-4 and ZAP-70 variants to the risk of type 1 diabetes in Tunisians
}}

{{PMID Auto
|PMID=20018057
|Title=Detecting single-nucleotide polymorphism by single-nucleotide polymorphism interactions in rheumatoid arthritis using a two-step approach with machine learning and a Bayesian threshold least absolute shrinkage and selection operator (LASSO) model.
|OA=1
}}

{{on chip | 23andMe v1}}
{{on chip | 23andMe v2}}
{{on chip | 23andMe v3}}
{{on chip | 23andMe v4}}
{{on chip | Affy GenomeWide 6}}
{{on chip | FTDNA2}}
{{on chip | FTDNA}}
{{on chip | HumanOmni1Quad}}
{{on chip | Illumina Human 1M}}