IthaID: 780

Names and Sequences

Functionality: Globin gene causative mutation Pathogenicity: Pathogenic / Likely Pathogenic
Common Name: CD 141 CTG>TGT [Arg>Cys] HGVS Name: HBA2:c.424C>T
Hb Name: Hb Nunobiki Protein Info: α2 141(HC3) Arg>Cys

Context nucleotide sequence:

Protein sequence:

Also known as:

Comments: Hb Nunobiki displays high oxygen affinity, relatively slow auto-oxidation, and normal stability in heat and isopropanol testing. It was initially detected in a 41-year-old Japanese male with borderline erythrocytosis as an α141 Arg>Cys change in either HBA1 or HBA2 gene by structural analysis. It was later detected by molecular testing in HBA2 in a Belgian woman with no Japanese background, as well as in 7 cases from four Spanish families with minimum levels of erythrocytosis [DOI: 10.4172/2157-7412.1000180]. The replacement of the last amino acid of the outer surface of the α chain C-terminal region terminal -Arginine (basic) with Cysteine (ambivalent), implies the modification of its electrical charge, and thus detection by any kind of electrophoresis system.

We follow the HGVS sequence variant nomenclature and IUPAC standards.


Hemoglobinopathy Group: Structural Haemoglobinopathy
Hemoglobinopathy Subgroup: α-chain variant
Allele Phenotype:N/A
Stability: N/A
Oxygen Affinity: Increased Oxygen Affinity
Associated Phenotypes: N/A


Chromosome: 16
Locus: NG_000006.1
Locus Location: 34458
Size: 1 bp
Located at: α2
Specific Location: Exon 3

Other details

Type of Mutation: Point-Mutation(Substitution)
Effect on Gene/Protein Function: Missense codons (Protein Structure)
Ethnic Origin: Japanese, Belgian, Spanish
Molecular mechanism: N/A
Inheritance: Recessive
DNA Sequence Determined: Yes


Disclaimer: The HPLC images are provided as an information resource only. Bio-Rad Laboratories, Inc and the ITHANET Portal disclaim responsibility and have no liability if this information is used for diagnostic or treatment purposes. D-10™ and VARIANT™ are registered trademarks of Bio-Rad Laboratories, Inc. and used with permission. Redistribution and use of the above material is allowed only with permission by Bio-Rad Laboratories, Inc. To access HPLC images and reports for different variants, use the IthaChrom tool.
ID Hb Variant Gene Instrument Method Area (%) Ret Time (min) Comments
220Hb Nunobikiα2D-10Dual Kit Program5.81.44Heterozygous. Increased oxygen affinity leading to a mild erythrocytosis.[PDF]
221Hb Nunobikiα2VARIANTβ-thal Short Program12.81.51Heterozygous. Increased oxygen affinity leading to a mild erythrocytosis.[PDF]
222Hb Nunobikiα2VARIANT IIβ-thal Short Program12.71.6Heterozygous. Increased oxygen affinity leading to a mild erythrocytosis.[PDF]
223Hb Nunobikiα2VARIANT IIDual Kit Program61.55Heterozygous. Increased oxygen affinity leading to a mild erythrocytosis.[PDF]

In silico pathogenicity prediction

Sequence Viewer

Note: The NCBI Sequence Viewer is not installed on the ITHANET servers but it is embedded in this page from the NCBI. Therefore, IthaGenes has no responsibility over any temporary unavailability of the service. In such a case, please Refresh the page or retry at a later stage. Otherwise, use this external link.

Publications / Origin

  1. Shimasaki S, A new hemoglobin variant, hemoglobin Nunobiki [alpha 141 (HC3) Arg----Cys]. Notable influence of the carboxy-terminal cysteine upon various physico-chemical characteristics of hemoglobin., J. Clin. Invest. , 75(2), 695-701, 1985 PubMed
  2. Kazanetz EG, Leonova JY, Huisman TH, van der Dijs FP, Smit JW, Hb Nunobiki or alpha 2 141 (HC3)Arg-->Cys beta 2 in a Belgian female results from a CGT-->TGT mutation in the alpha 2-globin gene., Hemoglobin, 20(4), 443-5, 1996 PubMed
  3. de la Fuente-Gonzalo F, Nieto JM, Villegas A, González FA, Martínez R, Ropero P, Characterization of deletional and non-deletional alpha globin variants in a large cohort from Spain between 2009 and 2014., Ann Hematol, 98(7), 1537-1545, 2019 PubMed
Created on 2010-06-16 16:13:16, Last reviewed on 2023-11-08 14:22:21 (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.