Open AccessDetection of Hb H disease caused by a novel mutation and ‐‐ SEA deletion using capillary electrophoresis
Author(s) -
Li Youqiong,
Liang Liang,
Tian Mao,
Qin Ting,
Wu Xin
Publication year - 2019
Publication title -
journal of clinical laboratory analysis
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.536
H-Index - 50
eISSN - 1098-2825
pISSN - 0887-8013
DOI - 10.1002/jcla.22949
Subject(s) - proband , capillary electrophoresis , sanger sequencing , mutation , microbiology and biotechnology , thalassemia , genotype , compound heterozygosity , biology , heterozygote advantage , genetics , anemia , medicine , gene
Background Hb H disease is a serious type of α‐thalassemia which cause moderate anemia while misdiagnosis by routine genetic analysis in a rare or novel Hb H disease. Methods The study was done on three patients and one fetus in a suspected Hb H disease family. Hb analysis was carried out using capillary electrophoresis (CE), and hematological analysis was conducted with an automated cell counter. Common α‐ and β‐thalassemia mutations were detected by routine genetic analysis (gap‐PCR and RDB‐PCR). Novel mutation diagnostic methods were based on DNA sequencing. Results Capillary electrophoresis revealed clinical feature of classic Hb H disease in the proband, and hematology analysis showed moderate anemia (Hb 87 g/L). But routine genetic analysis was found that it was only a heterozygote for the ‐‐ SEA deletion. DNA sequencing of α‐globin genes (α1 and α2) identified the breakpoints between nts 34162 and 34171 at α2 gene, named CD 90‐93 (‐AGCTTCGG) mutation. The genotype of proband and fetus was the same ‐‐ SEA /‐α CD90‐93 . His father was homozygous for the novel mutation (‐α CD90‐93 /‐α CD90‐93 ), and his mother was heterozygote for the ‐‐ SEA deletion. Conclusions Our study for the first time described the novel mutation CD 90‐93 (‐AGCTTCGG). CE is a way to avoid misdiagnosis of rare or novel Hb H disease.