{{Rsnum
|rsid=28934895
|Gene=BCKDHB
|Chromosome=6
|position=80168945
|Orientation=plus
|Summary= Maple Syrup Urine Disease
|geno1=(C;C)
|geno2=(C;G)
|geno3=(G;G)
|Gene_s=BCKDHB
|Assembly=GRCh38
|GenomeBuild=38.1
|dbSNPBuild=141
|Status=Merged
|Merged=79761867
}}[[rs28934895]], also known as R183P, is a mutation (rare SNP) in the branched chain keto acid dehydrogenase E1, beta polypeptide [[BCKDHB]] gene. The common allele is [[rs28934895]](G), encoding arginine (R) at amino acid position 183. 

With a frequency of about 1 in 100 among Jews of European descent, the much rarer [[rs28934895]](C) allele encodes a proline (P), and it is the most frequent mutation leading to [[Maple Syrup Urine Disease]], accounting for perhaps 90% of the mutations in this population group. However, by itself the mutation does not predict the severity of the disease; note also that only homozygotes ([[rs28934895]](C;C)) are at risk for the disease.{{PMID|11509994|OA=1
}}

This SNP is often included in screening panels for carriers of deleterious mutations among [[Ashkenazi Jews]], such as carrier screens for prospective parental couples.

{{omim
| id = 248611
| variant = 0002
| desc    = [[Maple Syrup Urine Disease]], CLASSIC, TYPE IB
| rsnum   = 28934895
}}

Note also that [[23andMe]] uses a different name for this SNP; in their terminology, [[rs28934895]] is called [[i3002808]].