GeneID: 4


Common Name: α1 Type: Gene
Chromosome: 16 (NC_000016.10) Locus: NG_000006.1 (α-locus)
HUGO Symbol: HBA1 Full Name: hemoglobin subunit alpha 1
Exons: 3 Introns: 2

The human alpha globin gene cluster located on chromosome 16 spans about 30 kb and includes seven loci: 5’-HBZ2-ΨHBZ1-ΨHBA2-ΨHBA1-HBA2-HBA1-θ-3’. The alpha-2 (HBA2) and alpha-1 (HBA1) coding sequences are identical. These genes differ slightly over the 5' untranslated region and the introns, but differ significantly over the 3' untranslated region. Two alpha chains plus two beta chains constitute HbA, which in normal adult life comprises about 97% of the total haemoglobin; alpha chains combine with delta chains to constitute HbA-2, which together with HbF (fetal haemoglobin) makes up the remaining 3% of adult haemoglobin. Alpha thalassaemias result from deletions of one or both of the HBA2 and HBA1 genes; some non-deletion alpha thalassaemias have also been reported. Three normal alpha genes give a silent carrier state. Two normal alpha genes result in microcytosis (so-called heterozygous alpha-thalassaemia). One normal alpha gene results in microcytosis and haemolysis. No normal alpha genes result in 'homozygous alpha-thalassaemia' manifested as fatal hydrops fetalis.

Synonyms: HBH , HBA-T3


Number of entries/variants: 418


Publications / Origin

  1. Higgs DR, Vickers MA, Wilkie AO, Pretorius IM, Jarman AP, Weatherall DJ, A review of the molecular genetics of the human alpha-globin gene cluster., Blood , 73(5), 1081-104, 1989
  2. Wilkie AO, Lamb J, Harris PC, Finney RD, Higgs DR, A truncated human chromosome 16 associated with alpha thalassaemia is stabilized by addition of telomeric repeat (TTAGGG)n., Nature, 346(6287), 868-71, 1990
Created on 2014-04-01 14:19:10, Last reviewed on 2016-04-28 11:26:29 (Show full history)

Disclaimer: The information on this website is provided as an information resource only and must not to be used as a substitute for professional diagnosis and treatment. The ITHANET Portal and IthaGenes are not responsible or liable for any advice, course of treatment, diagnosis or any other information, services or products that an individual obtains through this website.