rs13078881

A SNP in the BTD gene on chromosome 3. Its most notable genotype is C;C: Biotinidase deficiency; note ability to treat & variable penetrance

Gene
BTD
Location
Chr 315,645,186 (GRCh38)
Highest magnitude
6.7Very important
Tested on
23andMe, AncestryDNA
Minor allele frequency
2%

Genotypes

As shown in 23andMe and AncestryDNA files.

  1. C;CMost notableBadBiotinidase deficiency; note ability to treat & variable penetranceVery important · 6.70% of people
  2. C;GBadCarrier of a biotinidase deficiency mutationImportant · 3.01% of people
  3. G;GGoodcommon in clinvarTypical · 0.099% of people

On SNPedia: (C;C), (C;G), (G;G). Magnitude rates how notable a genotype is from 0 to 10, not how risky it is.

Frequency

Share of each genotype in 4 HapMap populations.

  • AverageC;C 0% C;G 1% G;G 99%
  • European ancestry (Utah)C;C 0% C;G 5% G;G 95%
  • Han Chinese (Beijing)C;C 0% C;G 0% G;G 100%
  • Japanese (Tokyo)C;C 0% C;G 0% G;G 100%
  • Yoruba (Nigeria)C;C 0% C;G 0% G;G 100%

Other BTD SNPs

All BTD SNPs

Notes

From SNPedia

Show notes, about 180 words

rs13078881, also known as c.1330G>C, p.Asp444His and D444H, represents a mutation in the BTD gene on chromosome 3. Inherited recessively, the rs13078881(C) allele is considered by ClinVar (and BabySeq) as a pathogenic mutation for biotinidase deficiency. However, it appears as if the D444H mutation results in 48% of normal enzyme activity, and if found in combination with a BTD gene mutation associated with profound deficiency, may result in partial biotinidase deficiency. Note that this condition is treatable; children with biotinidase deficiency identified early enough should remain asymptomatic if biotin therapy is instituted early. Profound biotinidase deficiency in two asymptomatic adults. Partial biotinidase deficiency is usually due to the D444H mutation in the biotinidase gene. Mutations causing profound biotinidase deficiency in children ascertained by newborn screening in the United States occur at different frequencies than in symptomatic children.

C;C

see rs13078881

C;G

Unaffected in absence of another BTD gene mutation; see rs13078881

Source and license

Adapted from rs13078881 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 Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice.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.