{{Rsnum
|rsid = 55964869
|Gene = ABO
|geno1 = (C;C)
|geno2 = (C;T)
|geno3 = (T;T)
|Orientation=minus
|ReferenceAllele=C
|Chromosome=9
|position=133256233
|Assembly=GRCh38
|GenomeBuild=38.1
|dbSNPBuild=141
|Gene_s=ABO
}}This SNP is in the [[ABO]] gene, and is therefore potentially useful in determing blood group type, such as through the use of [[genosets]]. 

This particular SNP can be useful in determining whether an ABO type A allele is more specifically an A1 type allele or an A2 type allele.

The more common allele (80% of A types on average) is A1, consistent with having a [[rs55964869]](C) allele, with the rarer A2 allele encoded by [[rs55964869]](T).

However, the key defining characteristic between an A1 and an A2 allele is the presence or absence of a deletion based on SNP [[rs8176750]].{{PMID|1520322}}

{{on chip | 23andMe v3}}
{{on chip | 23andMe v4}}