rs12948217
A SNP in the ASPA gene on chromosome 17. Its most notable genotype is A;A: Canavan disease (predicted); note issue with microarray data though
- Gene
- ASPA
- Location
- Chr 173,494,408 (GRCh38)
- Highest magnitude
- 8.0Very important
- Tested on
- 23andMe, AncestryDNA
- Minor allele frequency
- 21%
Genotypes
As shown in 23andMe and AncestryDNA files.
- A;AMost notableBadCanavan disease (predicted); note issue with microarray data though
- A;CBadCarrier of a Canavan disease mutation; note issue with microarray data though
- A;TBadCarrier of a Canavan disease mutation
- C;CGoodcommon in clinvar
- C;TGoodNo summary available.
- T;TGoodNo summary available.
On SNPedia: (A;A), (A;C), (A;T), (C;C), (C;T), (T;T). Magnitude rates how notable a genotype is from 0 to 10, not how risky it is.
Related
Conditions, medicines and genes
Other ASPA SNPs
- rs28940279C;CCanavan disease (predicted)Very important
- rs28940574A;ACanavan disease (predicted)Very important
- rs104894548C;CCanavan disease (predicted)Very important
- rs104894549A;ACanavan disease (predicted)Very important
- rs104894550G;GCanavan disease (predicted)Very important
- rs104894551G;GCanavan disease (predicted)Very important
- rs104894552T;TCanavan disease (predicted)Very important
- rs199565861T;TCanavan disease (predicted)Very important
Notes
From SNPedia
Show notes, about 220 words
rs12948217, also known as c.693C>A, Y231X or Tyr231Ter, is a SNP in the ASPA gene. Note that a benign variant of this SNP (c.693C>T) also exists as discussed below. Only the A allele at rs12948217 confers risk to Canavan disease. A person with the CC, CT, or TT alleles is not a carrier; someone with the AC or AT alleles is a carrier; and people with two AA alleles are affected with the disease. Note that due for technical reasons, the vast majority of direct-to-consumer companies using DNA chips (microarrays) for genotyping do not distinguish the benign T allele from the pathogenic A allele. As a result, raw data from these companies that reports (A;C) and especially (A;A) is quite likely to actually represent the benign (C;T) or perhaps (T;T) genotypes. This type of error applies only to data derived from microarrays (specifically, Illumina microarrays such as those used by 23andMe and Ancestry) and does not apply to data generated by sequencing.
A;A
See discussion at Canavan disease and links via main SNP page. Note: several years ago, certain genotyping companies may have routinely misreported results for this SNP, and so an abundance of caution is recommended for anyone receiving this genotype in their raw data.
A;C
Unaffected in absence of a second ASPA gene mutation.
A;T
Unaffected in absence of a second ASPA gene mutation.
Source and license
Adapted from rs12948217 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.