The prevalence and molecular characterization of (δβ)⁰‐thalassemia and hereditary persistence of fetal hemoglobin in the Chinese Zhuang population

Abstract

ObjectiveTo reveal the prevalence and molecular characterization of (δβ)0‐thalassemia [(δβ)0‐thal] and hereditary persistence of fetal hemoglobin (HPFH) in the Chinese Zhuang population.MethodsA total of 105 subjects with fetal hemoglobin (Hb F) level ≥5% from 14 204 unrelated ones were selected for the study. Multiplex ligation dependent probe amplification was firstly used to analyze dosage changes of the β‐globin gene cluster for associated with (δβ)0‐thal and HPFH mutations. The gap polymerase chain reaction was then performed to identify the deletions using the respective flanking primers. Hematologic data were recorded and correlated with the molecular findings.ResultsTwenty‐one (0.15%) subjects were diagnosed with Chinese Gγ(Aγδβ)0‐thal. Nine (0.06%) were diagnosed with Southeast Asia HPFH (SEA‐HPFH) deletion. Seventy‐five (0.53%) cases remained uncharacterized. Three genotypes for Chinese Gγ(Aγδβ)0‐thal and SEA‐HPFH deletion were identified, respectively. The genotype‐phenotype relationships were discussed.ConclusionOur study for the first time demonstrated that (δβ)0 and HPFH were not rare events, and molecular characterized Gγ(Aγδβ)0‐thal and HFPH mutations in the Chinese Zhuang population. The findings in our study will be useful in genetic counseling and prenatal diagnostic service of β‐thalassemia in this populations.

Molecular epidemiology and hematologic characterization of δβ-thalassemia and hereditary persistence of fetal hemoglobin in 125,661 families of greater Guangzhou area, the metropolis of southern China

“…To date, the Taiwanese deletion has only been reported as the case study , [18,19]. Compared to the three types, that is, Chinese G γ ( A γδβ) 0 -thal, SEA-HPFH and A γ-196 C-T mutation [9,10,20], the individual with the Taiwanese deletion showed higher HbA2 levels than 6% of our study cohort. This higher HbA2 level may due to deletion of the βglobin gene promoter.…”

“…Chinese G γ ( A γδβ) 0 thalassemia and SEA-HPFH are the most common deletional (δβ) 0 -thal/HPFH disorders in this region. The prevalence of these two disorders was lower than that in the Chinese Zhuang population but higher than that in the Chinese Hakka and Yunnan populations [9][10][11]. These differences may be caused by the population composition, which is rather homogeneous in those regions.…”

“…Table 1 lists those two β-globin cluster deletions and their associated phenotypes in southern China. The prevalence of deletional HPFH/δβ-thalassemia was reported in Yunnan, Guangdong and Guangxi provinces [9,10]. This prevalence was highest in the Guangxi Zhuang Autonomous Region, reaching 0.21%, while it was lower than 0.002% in Hakka People living in the Guangdong Meizhou areas [11].…”

Molecular Epidemiology and Hematologic Characterizationof δβ-thalassemia and Hereditary Persistence of Fetal Hemoglobin in 125661 Families of Greater Guangzhou Area, the metropolis of Southern China

“…To date, the Taiwanese deletion has only been reported as the case study , [18,19]. Compared to the three types, that is, Chinese G γ( A γδβ) 0 -thal, SEA-HPFH and A γ-196 C-T mutation [9,10,20], the individual with the Taiwanese deletion showed higher HbA2 levels than 6% of our study cohort. This higher HbA2 level may due to deletion of the β-globin gene promoter.…”

“…Table 1 lists those two β-globin cluster deletions and their associated phenotypes in southern China. The prevalence of deletional HPFH/δβthalassemia was reported in Yunnan, Guangdong and Guangxi provinces [9,10]. This prevalence was highest in the Guangxi Zhuang Autonomous Region, reaching 0.21%, while it was lower than 0.002% in Hakka People living in the Guangdong Meizhou areas [11].…”