IthaID: 365

We follow the HGVS sequence variant nomenclature and IUPAC standards.

Comments: The 2 nucleotide deletion c.94_95delAG was found on a chromosome that carries the -3.7 kb deletion (-α3.7) [IthaD:300]. The deletion of 'AG' on codon 31 in exon 1 creates a frameshift and premature truncation of the α-globin protein after 25 amino acids (p.Arg31AspfsX25) at codon 55. The in cis variation presented with mild hypochromic microcytic anaemia consistent with α-thalassaemia trait in the heterozygous state and with HbH disease in the presence of Hb G-Philadelphia [IthaID:596]. HGVS name reports deletion breakpoints in -α3.7 (type I) [IthaID: 300] and should be used with caution.

Heterozygous records (preview in IthaPhen)

1. Rieder RF, Woodbury DH, Rucknagel DL, The interaction of alpha-thalassaemia and haemoglobin G Philadelphia., Br J Haematol, 32(2), 159-65, 1976 PubMed
2. Sancar GB, Tatsis B, Cedeno MM, Rieder RF, Proportion of hemoglobin G Philadelphia (alpha 268 Asn leads to Lys beta 2) in heterozygotes is determined by alpha-globin gene deletions., Proc Natl Acad Sci U S A, 77(11), 6874-8, 1980 PubMed
3. Safaya S, Rieder RF, Dysfunctional alpha-globin gene in hemoglobin H disease in blacks. A dinucleotide deletion produces a frameshift and a termination codon., The Journal of biological chemistry, 263(9), 4328-32, 1988 PubMed
4. Zhao P, Buller-Burckle AM, Peng M, Anderson A, Han ZJ, Gallivan MV, Secondary mutation (c.94_95delAG) in a -α3.7 allele associated with Hb H disease in two unrelated African American individuals homozygous for the -α(3.7) deletion (-α3.7/-α3.7T)., Hemoglobin , 36(1), 103-7, 2012 PubMed