IthaID: 300

We follow the HGVS sequence variant nomenclature and IUPAC standards.

Comments: Rightward crossover between misaligned homologous Z boxes leads to the deletion of 3.7 kb DNA on one chromosome and the reciprocal triplicated α genes [IthaID: 2561] on another chromosome. The 3.7 kb deletion extends from the intron II of the α2 gene down to the intron II of the α1 gene, creating a single functional (fusion) gene. View [PMID: 14500599] for a schematic representation of the crossover between mispaired Z boxes. Prior to the exact deletion breakpoints analysis of α3.7 subtypes [PMID: 31199903], HGVS name of this variant was NG_000006.1:g.34164_37967del3804.

Heterozygous records (preview in IthaPhen)

1. Embury SH, Miller JA, Dozy AM, Kan YW, Chan V, Todd D, Two different molecular organizations account for the single alpha-globin gene of the alpha-thalassemia-2 genotype., The Journal of clinical investigation, 66(6), 1319-25, 1980 PubMed
2. Wang W, Ma ES, Chan AY, Prior J, Erber WN, Chan LC, Chui DH, Chong SS, Single-tube multiplex-PCR screen for anti-3.7 and anti-4.2 alpha-globin gene triplications., Clin. Chem., 49(10), 1679-82, 2003 PubMed
3. Borgio JF, Abdulazeez S, Almandil NB, Naserullah ZA, Al-Jarrash S, Al-Suliman AM, Elfakharay HI, Qaw FS, Alabdrabalnabi FI, Alkhalifah MA, Shakil Akhtar M, Qutub H, Al-Ali AK, The ‑α3.7 deletion in α‑globin genes increases the concentration of fetal hemoglobin and hemoglobin A2 in a Saudi Arabian population., Mol Med Rep, 17(1), 1879-1884, 2018 PubMed
4. Charoenwijitkul T, Singha K, Fucharoen G, Sanchaisuriya K, Thepphitak P, Wintachai P, Karnpean R, Fucharoen S, Molecular characteristics of α-thalassemia (3.7 kb deletion) in Southeast Asia: Molecular subtypes, haplotypic heterogeneity, multiple founder effects and laboratory diagnostics., Clin Biochem, 71(0), 31-37, 2019 PubMed