rs79761867
A SNP in the BCKDHB gene on chromosome 6. Its most notable genotype is C;C: Maple Syrup Urine disease
- Gene
- BCKDHB
- Location
- Chr 680,168,945 (GRCh38)
- Highest magnitude
- 5.0Very important
- Tested on
- AncestryDNA
Genotypes
As shown in 23andMe and AncestryDNA files.
- C;CMost notableBadMaple Syrup Urine disease
- C;GBadcarrier of Maple Syrup Urine disorder allele
- G;GGoodcommon in clinvar
On SNPedia: (C;C), (C;G), (G;G). Magnitude rates how notable a genotype is from 0 to 10, not how risky it is.
Related
Conditions, medicines and genes
Other BCKDHB SNPs
Notes
From SNPedia
Show notes, about 150 words
rs79761867, formerly known as rs28934895 and more commonly 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. This SNP is often included in screening panels for carriers of deleterious mutations among Ashkenazi Jews, such as carrier screens for prospective parental couples. 23andMe name: i3002808
Source and license
Adapted from rs79761867 on SNPedia, using a snapshot taken October 16, 2026. SNPedia content is shared under CC BY-NC-SA 3.0 US, and this page is shared under the same license.
SNPedia is a community-edited wiki. Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice. Magnitude is a community rating of how interesting a genotype is, not a risk score.