rs33971440
A SNP in the HBB gene on chromosome 11. Its most notable genotype is T;T: Beta Thalassemia major; Hemoglobin beta-zero; possibly transfusion dependent
- Gene
- HBB
- Location
- Chr 115,226,929 (GRCh38)
- Highest magnitude
- 5.5Very important
- Tested on
- 23andMe
- Minor allele frequency
- <1%
Genotypes
Plus strand, as in 23andMe and AncestryDNA files.
- T;TMost notableBadBeta Thalassemia major; Hemoglobin beta-zero; possibly transfusion dependent
- C;TBadBeta Thalassemia carrier; Hemoglobin beta-zero mutation; anemia possible
- C;CGoodcommon in clinvar
SNPedia records rs33971440 on the minus strand: (A;A), (A;G), (G;G). Magnitude rates how notable a genotype is from 0 to 10, not how risky it is.
Related
Other HBB SNPs
- rs11549407A;ABeta Thalassemia major; Hemoglobin beta-zeroVery important
- rs33945777T;TBeta Thalassemia major; Hemoglobin beta-zero; possibly transfusion dependentVery important
- rs33960103G;GBeta Thalassemia major; Hemoglobin beta-zero; possibly transfusion dependentVery important
- rs33974936T;TBeta Thalassemia major; Hemoglobin beta-zeroVery important
- rs33986703A;ABeta Thalassemia major; Hemoglobin beta-zero; possibly transfusion dependentVery important
- rs34716011T;TBeta Thalassemia major; Hemoglobin beta-zero; possibly transfusion dependentVery important
- rs34889882-;-Beta Thalassemia major; Hemoglobin beta-zero; possibly transfusion dependentVery important
- rs35497102-;-Beta Thalassemia major; Hemoglobin beta-zero; possibly transfusion dependentVery important
Notes
From SNPedia
Notes
T;T
see HBB
C;T
see discussion at HBB
Source and license
Adapted from rs33971440 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 Its entries can be incomplete, out of date or wrong, and nothing here is a diagnosis or medical advice.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.