First report of the spectrum of δ‐globin gene mutations in Omani subjects – identification of novel mutations

Abstract

These delta mutations exhibit low HbA2 either due to a shift in the HPLC position or due to their bona fide thalassemic feature. Two mutations, namely cd142 G-->C (GCC to CCC, Ala to Pro) and stop codon cd147 G-->T (stop to Leu with elongation of 15 amino acids), herein first reported are novel. Coexistence of IDA could lead to erroneous diagnostic interpretation unless it is specifically looked for.

First report of the spectrum of δ‐globin gene mutations among women of reproductive age in Fujian area—Discrimination of δ‐thalassemia, α‐thalassemia, and Iron Deficiency Anemia

“…A total of 4 792 women of reproductive age (between 15 and 49 years) in Fujian subjects were screened using capillary electrophoresis from January 2017 to December 2018, and 166 subjects with HbA 2 levels below 2.0% with normal or reduced hematological parameters (mean corpuscular volume (MCV) ＜82.0 fL and mean corpuscular Hb (MCH)＜27.0 pg] 13,15‐18 at the Outpatient Department of Fujian Provincial Maternity and Children's Hospital were recruited for this study and further examined with red cell parameters and tested for thalassemia and ferritin level. The recruited subjects had a mean age of 33 years (range from 15 to 49 years) and came from 9 cities across the province.…”

“…Many reports showed that δ-thalassemia mutations decreased HbA 2 levels (2% in heterozygote or ≤0.6% in homozygote subjects). 13,[15][16][17][18] Therefore, we prospectively enrolled a cohort of Fujian subjects with HbA 2 levels below 2.0% and report for the first time the spectrum of δ-thalassemia mutations, discrimination of α-thalassemia, and IDA in this cohort. Such a study may provide more data for genetic counseling and accurate prenatal diagnosis in this region to reduce the birth of babies with thalassemia major.…”

“…Nevertheless, so far, there are no reports specifically investigating the prevalence, molecular characterization, and phenotype of δ‐thalassemia mutations in this region, which will aid in genetic counseling and prenatal diagnosis. Many reports showed that δ‐thalassemia mutations decreased HbA 2 levels (2% in heterozygote or ≤0.6% in homozygote subjects) 13,15‐18 …”

A Novel Mutation of the δ-Globin Gene in an Asymptomatic 30-Year-Old Female

“…1). Previously, Alkindi et al [6] described for the first time a TGA>TTA (stop to Leu) mutation at cd147 in a heterozygous state in a subject who was also homozygous for -α 3.7 allele. The subject was also asymptomatic and was identified during a screening for β-thalassemia screening.…”

“…Both mutations cause an elongation of 15 amino acids in the protein carboxy terminal. We hypothesize that this elongated δ-globin, similarly to the elongated polypeptides α-globin and β-globin, would be unstable [6]. Certainly, the number of mutations on the δ-gene has increased greatly and about 117 δ-globin gene mutations have been reported so far (http://globin.cse.psu.edu/hbvar/menu.html) [7].…”