IthaID: 473
Names and Sequences
| Functionality: | Globin gene causative mutation | Pathogenicity: | Variant of Uncertain Significance |
|---|---|---|---|
| Common Name: | CD 19 GCG>GAG [Ala>Glu] | HGVS Name: | HBA2:c.59C>A |
| Hb Name: | Hb J-Tashikuergan | Protein Info: | α2 19(AB1) Ala>Glu |
| Also known as: |
We follow the
HGVS sequence variant nomenclature
and
IUPAC standards.
Context nucleotide sequence:
AAGGCCGCCTGGGGTAAGGTCGGCG [C/A] GCACGCTGGCGAGTATGGTGCGGAG (Strand: +)
Protein sequence:
MVLSPADKTNVKAAWGKVGEHAGEYGAEALERMFLSFPTTKTYFPHFDLSHGSAQVKGHGKKVADALTNAVAHVDDMPNALSALSDLHAHKLRVDPVNFKLLSHCLLVTLAAHLPAEFTPAVHASLDKFLASVSTVLTSKYR
Comments: Initially reported in three unrelated fmilies of the Tajike ethnic group and identified by peptide mapping and amino acid analysis as a Ala > Glu change in the 19th position of the α-chain [PMID: 6548207]. This same amino acid change was reported in the Silk Road region of NW China [PMID: 2265836]. Detected by Sanger sequencing in the HBA2 gene and found to co-elute with HbA1c [PMID: 33315479]. Residue α19 (AB) is in the external and non-helical segment of the α-chain and is not involved in either haem or interchain contacts. The Ala>Glu change at this residue is therefore not expected to be associated with haemoglobin instability or to affect haem binding or oxygen dissociation.
Phenotype
| Hemoglobinopathy Group: | Structural Haemoglobinopathy |
|---|---|
| Hemoglobinopathy Subgroup: | α-chain variant |
| Allele Phenotype: | N/A |
| Stability: | N/A |
| Oxygen Affinity: | N/A |
| Associated Phenotypes: | N/A |
Location
| Chromosome: | 16 |
|---|---|
| Locus: | NG_000006.1 |
| Locus Location: | 33834 |
| Size: | 1 bp |
| Located at: | α2 |
| Specific Location: | Exon 1 |
Other details
| Type of Mutation: | Point-Mutation(Substitution) |
|---|---|
| Effect on Gene/Protein Function: | Missense codons (Protein Structure) |
| Ethnic Origin: | Tajiks, Chinese |
| Molecular mechanism: | N/A |
| Inheritance: | Recessive |
| DNA Sequence Determined: | Yes |
In silico pathogenicity prediction
Sequence Viewer
Publications / Origin
- Li HJ, Liu DX, Liu ZG, Li P, Li L, Chen J, Hou SZ, A new fast-moving hemoglobin variant, Hb J-Tashikuergan alpha 19(AB1) Ala----Glu., Hemoglobin , 8(4), 391-5, 1984 PubMed
- Li HJ, Zhao XN, Qin F, Li HW, Li L, He XJ, Chang XS, Li ZM, Liang KX, Xing FL, Abnormal hemoglobins in the Silk Road region of China., Hum. Genet. , 86(2), 231-5, 1990 PubMed
- Henderson SJ, Timbs AT, McCarthy J, Gallienne AE, Proven M, Rugless MJ, Lopez H, Eglinton J, Dziedzic D, Beardsall M, Khalil MS, Old JM, Ten Years of Routine α- and β-Globin Gene Sequencing in UK Hemoglobinopathy Referrals Reveals 60 Novel Mutations., Hemoglobin , 40(2), 75-84, 2016 PubMed
- Xu J, Zhong Z, Deng Y, Unexpected HbA results in the presence of three rare hemoglobin variants., Scand J Clin Lab Invest, 81(1), 59-64, 2021 PubMed