HBA2 Chromosome 16
Hemoglobin subunit alpha 2
Upload your DNA to see your personal genotypes for variants in HBA2.
What This Gene Does
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]
Gene Info
Gene Group
"Hemoglobin subunits|Proteins encoded by multiple genes"
Locus Type
gene with protein product
Location
16p13.3
Ensembl
ENSG00000188536
Associated Conditions (47)
alpha Thalassemia
HBA2-related disorder
Heinz body anemia
Hemoglobin H disease
Erythrocytosis
familial
7
HEMOGLOBIN I (BURLINGTON)
HEMOGLOBIN I (PHILADELPHIA)
HEMOGLOBIN I (SKAMANIA)
HEMOGLOBIN I (TEXAS)
HEMOGLOBIN I
HEMOGLOBIN INKSTER
HEMOGLOBIN EVANS
HEMOGLOBIN SUN PRAIRIE
HEMOGLOBIN WAYNE
HEMOGLOBIN H HYDROPS FETALIS SYNDROME
HEMOGLOBIN ZURICH ALBISRIEDEN
Alpha-thalassemia
Dutch type
+27 more conditions
Key Variants
RS1025977498
Conflicting classifications of pathogenicity
Health Risk
RS1188584832
Conflicting classifications of pathogenicity
Health Risk
RS1363099908
Conflicting classifications of pathogenicity
Health Risk
RS1455865276
Conflicting classifications of pathogenicity
Health Risk
RS1468615416
Conflicting classifications of pathogenicity
alpha Thalassemia, alpha Thalassemia
Health Risk
RS1567163204
Conflicting classifications of pathogenicity
Health Risk
RS1596570272
Conflicting classifications of pathogenicity
alpha Thalassemia, alpha Thalassemia
Health Risk
RS267607269
Conflicting classifications of pathogenicity
Health Risk
RS281860607
Conflicting classifications of pathogenicity
Health Risk
RS281860609
Conflicting classifications of pathogenicity
Health Risk
RS281860615
Conflicting classifications of pathogenicity
HBA2-related disorder, HBA2-related disorder
Health Risk
RS281864809
Conflicting classifications of pathogenicity
Health Risk
All Variants (88)
| RSID | Category | Clinical Significance | Conditions |
|---|---|---|---|
| RS2142018005 | Health Risk | Pathogenic | Heinz body anemia, Heinz body anemia |
| RS2505431550 | Health Risk | Pathogenic | alpha Thalassemia, alpha Thalassemia |
| RS281864539 | Health Risk | Pathogenic | alpha Thalassemia, alpha Thalassemia |
| RS281864829 | Health Risk | Pathogenic | Thalassemia, Thalassemia |
| RS281864846 | Health Risk | Pathogenic | Non-immune hydrops fetalis, HEMOGLOBIN H HYDROPS FETALIS SYNDROME, alpha Thalassemia |
| RS281864889 | Health Risk | Pathogenic | alpha Thalassemia, alpha Thalassemia |
| RS33933481 | Health Risk | Pathogenic | HEMOGLOBIN TARRANT, Heinz body anemia, Erythrocytosis |
| RS41341344 | Health Risk | Pathogenic | HEMOGLOBIN AGRINIO, Hemoglobin H disease, nondeletional |
| RS41397847 | Health Risk | Pathogenic | Hemoglobin Quong Sze, alpha Thalassemia, Heinz body anemia |
| RS41412046 | Health Risk | Pathogenic | Hemoglobin H disease, nondeletional, alpha Thalassemia |
| RS41457746 | Health Risk | Pathogenic | Alpha-thalassemia, Dutch type, alpha Thalassemia |
| RS41474145 | Health Risk | Pathogenic | alpha Thalassemia, Heinz body anemia, Hemoglobin H disease |
| RS41515552 | Health Risk | Pathogenic | HBA2-related disorder, HBA2-related disorder |
| RS587776826 | Health Risk | Pathogenic | Alpha trait thalassemia, Alpha trait thalassemia |
| RS587776828 | Health Risk | Pathogenic | Alpha-thalassemia, Hmong type, alpha Thalassemia |
| RS63750158 | Health Risk | Pathogenic | alpha Thalassemia, alpha Thalassemia |
| RS63750367 | Health Risk | Pathogenic | alpha Thalassemia, alpha Thalassemia |
| RS63750678 | Health Risk | Pathogenic | Hemoglobin H disease, nondeletional, alpha Thalassemia |
| RS63751269 | Health Risk | Pathogenic | alpha Thalassemia, Hemoglobin H disease, beta Thalassemia |
| RS746988006 | Health Risk | Pathogenic | — |
| RS886041399 | Health Risk | Pathogenic | alpha Thalassemia, Erythrocytosis, familial |
| RS33983416 | Health Risk | Pathogenic; other | HEMOGLOBIN COLUMBIA MISSOURI, Erythrocytosis, familial |
| RS33985574 | Health Risk | Pathogenic; other | HEMOGLOBIN J (BUDA), Erythrocytosis, familial |
| RS41361546 | Health Risk | Pathogenic; other | HEMOGLOBIN HANAMAKI, Erythrocytosis, familial |
| RS41479844 | Health Risk | Pathogenic; other | HEMOGLOBIN SUAN-DOK, alpha Thalassemia, HEMOGLOBIN SUAN-DOK |
| RS1262943621 | Health Risk | Pathogenic/Likely pathogenic | — |
| RS1263969213 | Health Risk | Pathogenic/Likely pathogenic | alpha Thalassemia, Hemoglobin H disease, Heinz body anemia |
| RS1270810159 | Health Risk | Pathogenic/Likely pathogenic | alpha Thalassemia, Heinz body anemia, Hemoglobin H disease |
| RS281864550 | Health Risk | Pathogenic/Likely pathogenic | alpha Thalassemia, Hemoglobin H disease, Heinz body anemia |
| RS281864834 | Health Risk | Pathogenic/Likely pathogenic | HEMOGLOBIN L (FERRARA), HEMOGLOBIN SINAI, HEMOGLOBIN HASHARON |
| RS281864840 | Health Risk | Pathogenic/Likely pathogenic | — |
| RS281864878 | Health Risk | Pathogenic/Likely pathogenic | — |
| RS41321345 | Health Risk | Pathogenic/Likely pathogenic | HEMOGLOBIN KOYA DORA, alpha Thalassemia, Erythrocytosis |
| RS41323248 | Health Risk | Pathogenic/Likely pathogenic | HEMOGLOBIN DARTMOUTH, alpha Thalassemia, HEMOGLOBIN DARTMOUTH |
| RS41417548 | Health Risk | Pathogenic/Likely pathogenic | HEMOGLOBIN SALLANCHES, Hemoglobin H disease, nondeletional |
| RS41464951 | Health Risk | Pathogenic/Likely pathogenic | Hemoglobin constant spring, Hemoglobin H disease, nondeletional |
| RS63750067 | Health Risk | Pathogenic/Likely pathogenic | Alpha-thalassemia-2, nondeletional, Hemoglobin H disease |
| RS63751268 | Health Risk | Pathogenic/Likely pathogenic | alpha Thalassemia, Heinz body anemia, Hemoglobin H disease |