HBA2 hemoglobin subunit alpha 2
Gene ID: 3040, updated on 30-Oct-2024Gene type: protein coding
Also known as: HBH; ECYT7; HBA-T2
- See all available tests in GTR for this gene
- Go to complete Gene record for HBA2
- Go to Variation Viewer for HBA2 variants
Summary
The human alpha globin gene cluster located on chromosome 16 spans about 30 kb and includes seven loci: 5'- zeta - pseudozeta - mu - pseudoalpha-1 - alpha-2 - alpha-1 - theta - 3'. The alpha-2 (HBA2) and alpha-1 (HBA1) coding sequences are identical. These genes differ slightly over the 5' untranslated regions and the introns, but they differ significantly over the 3' untranslated regions. Two alpha chains plus two beta chains constitute HbA, which in normal adult life comprises about 97% of the total hemoglobin; alpha chains combine with delta chains to constitute HbA-2, which with HbF (fetal hemoglobin) makes up the remaining 3% of adult hemoglobin. Alpha thalassemias result from deletions of each of the alpha genes as well as deletions of both HBA2 and HBA1; some nondeletion alpha thalassemias have also been reported. [provided by RefSeq, Jul 2008]
Associated conditions
See all available tests in GTR for this gene
| Description | Tests |
|---|---|
| alpha Thalassemia | See labs |
| Erythrocytosis, familial, 7 | See labs |
| Genome-wide association study of hematological and biochemical traits in a Japanese population. GeneReviews: Not available | |
| Heinz body anemia | See labs |
| Hemoglobin H disease | See labs |
Genomic context
- Location:
- 16p13.3
- Sequence:
- Chromosome: 16; NC_000016.10 (172876..173710)
- Total number of exons:
- 3
Variation
| Resource | Links for this gene |
|---|---|
| ClinVar | Variants reported to ClinVar |
| dbVar | Studies and variants |
| SNP | Variation Viewer for HBA2 variants |
| Genome viewer | Explore NCBI-annotated and select non-NCBI annotated genome assemblies |
- ClinVarRelated medical variations
- dbVarLink from Gene to dbVar
- HBA2 @ LOVD
- HbVar: A Database of Human Hemoglobin Variants and Thalassemias
- MedGenRelated information in MedGen
- OMIMLink to related OMIM entry
- PubMed (OMIM)Gene links to PubMed derived from omim_pubmed_cited links
- RefSeq RNAsLink to Nucleotide RefSeq RNAs
- RefSeqGeneLink to Nucleotide RefSeqGenes
- Variation ViewerRelated Variants
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