1.A novel double heterozygote of HBB c.219T>A;220G>T: gene diagnosis and pedigree analysis.
Jiezhong LV ; Zhaofan LUO ; Jianpei FANG ; Tao DU ; Hongman XUE ; Yong LIU ; Jianping ZHANG
Chinese Journal of Medical Genetics 2017;34(4):538-541
OBJECTIVETo identify a novel hemoglobinopathy applied by direct sequencing and clone sequencing.
METHODSEDTA anticoagulated blood of proband and his parents were analyzed by hematology analyzers and Capillarys hemoglobin electrophoresis (CE). Then thalassemia genetypes were screened by gap-PCR and reverse dot blot (RDB). Proband was suspected with abnormal hemoglobin combine alpha beta compound thalassemia. The mutation of beta-globin was identified by direct sequencing and clone sequencing.
RESULTSHb analysis showed that probands Hb A2 variant was eluted in Z (C) zone and his father's in Z (A2) zone on CE,and proband's mother elevated HbA2 of 4.6%. Screened by RDB, the proband was CD71-72(+A) homozygote and showed the mismatch with his parents. Through direct sequencing and clone sequencing, we deduced that our proband inherited the mutations of HBB c.[219T>A;220G>T] from his father and inherited the Southeast-Asian deletion and HBB c.216-217insA from his mother.
CONCLUSIONA novel double heterozygote of HBB c.[219T>A; 220G>T] was identified in south China. This mutation enriches the beta-thalassemia gene mutation spectrum in Chinese population.
Asian Continental Ancestry Group ; genetics ; Child, Preschool ; Hemoglobins ; genetics ; Hemoglobins, Abnormal ; genetics ; Heterozygote ; Humans ; Male ; Mutation ; genetics ; Pedigree ; Thalassemia ; genetics ; beta-Globins ; genetics