Compound heterozygosity for hemoglobin variant Hb-Broomhill and the Southeast Asian α-thalassemia deletion does not worsen outcome: a case report of two unrelated patients

• Published in: Journal of international medical research Vol. 48; no. 11; p. 300060520967825
• Main Authors: Qin, Danqing, Du, Li, Wang, Jicheng, Yao, Cuize, Guo, Hao, Yuan, Tenglong, Liang, Jie, Yin, Aihua
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01.11.2020; Sage Publications Ltd; SAGE Publishing
• Subjects: alpha-Thalassemia - diagnosis; alpha-Thalassemia - genetics; Asian Continental Ancestry Group - genetics; Blood diseases; Capillary electrophoresis; Case Report; Case reports; Genotype; Genotype & phenotype; Hematologic Tests; Hemoglobin; Hemoglobins, Abnormal - genetics; Humans; Compound heterozygosity; hemoglobin Broomhill; Sanger sequencing; Southeast Asian α-thalassemia deletion; capillary electrophoresis; hemoglobin variant
• ISSN: 0300-0605; 1473-2300; 1473-2300
• DOI: 10.1177/0300060520967825

We report two unrelated cases of compound heterozygosity for hemoglobin (Hb) variant Broomhill and the Southeast Asian (- - SEA/) α-thalassemia deletion, whose clinical features and laboratory findings have never been reported. Hematological analyses revealed abnormal values for both cases as α-thalassemia traits, and capillary electrophoresis suggested an abnormal peak that was incompletely separated from the Hb A peak. A suspension array system and Sanger sequencing were used to characterize the genotypes. Sanger sequencing confirmed the presence of Hb Broomhill [α114(GH2)Pro→Ala; HBA1: c.343C>G]. Eventually, both cases were accurately diagnosed as compound heterozygotes for Hb Broomhill and the (- - SEA/) α-thalassemia deletion, which is the first known report of these variants. This information will be useful when providing appropriate genetic counselling and prenatal diagnosis.