Prevalence and genetic analysis of α-thalassemia and β-thalassemia in Chongqing area of China.
OBJECTIVE
Thalassemia is one of the most common hereditary disorders. This study aimed to investigate the prevalence of thalassemia and the mutation spectrum in Chongqing, the southern area of China.


METHODS
A total of 1057 children were recruited from Chongqing. Hematological parameters were examined and globin genes were genetically analyzed.


RESULTS
The total frequency of thalassemia carriers was 7.76% in this group of children. Among these, α-thalassemia was 5.20%, β-thalassemia was 1.99% and abnormal hemoglobin variant was 0.57%. Furthermore, 24 cases of α-triplication were detected, frequency of which was 2.55%. The true prevalence of silent α-thalassemia was first reported in this study. In addition, six novel mutations that give rise to α-thalassemia and two rare abnormal hemoglobin variants were first identified in Chinese population.


CONCLUSIONS
Our data suggested that the population in Chongqing are at high risk of α- and β-thalassemia. The findings will be useful for genetic counseling and the prevention of severe thalassemias in this area.
Division of Hematology, Children's Hospital, Chongqing Medical University, the Ministry of Education Key Laboratory of Child development and Disorders, Chongqing 400014, China; Key laboratory of Pediatrics in Chongqing, Chongqing 400014, China; Chongqing International Science and Technology Cooperation Center for Child Development and Disorders, Chongqing 400014, China.
Xiu-Yun
XY
Yao
Jie
J
Yu
Shi-Ping
SP
Chen
Jian-Wen
JW
Xiao
Qi-Chen
QC
Zheng
Hai-Yan
HY
Liu
Lei
L
Zhang
Ying
Y
Xian
Lin
L
Zou
D002648:Child; D002675:Child, Preschool; D002681:China / Q000453:epidemiology; D005260:Female; D005787:Gene Frequency; D006455:Hemoglobins, Abnormal / Q000235:genetics; D006579:Heterozygote; D006801:Humans; D008297:Male; D009154:Mutation; D055542:alpha-Globins / Q000235:genetics; D017085:alpha-Thalassemia / Q000453:epidemiology* / Q000235:genetics*; D017086:beta-Thalassemia / Q000453:epidemiology* / Q000235:genetics*
D006455:Hemoglobins, Abnormal; D055542:alpha-Globins
CD; DNA; EDTA; Gap polymerase chain reaction; Gap-PCR; Globin gene; Hb; Hb A(2); Hb F; Hemoglobin A(2); Hemoglobin F; IVS; MCH; MCV; Messenger Ribonucleic Acid; Microliter; Milliliter; Mutation; PCR; Polymerase chain reaction; Prevalence; Quantitative real-time PCR; RBC; RDB; RDW; RT-PCR; Red blood cell count; Red cell distribution width; Reverse dot blot; Revolutions per minute; Thalassemia; UTR; Variants; base pair; bp; codon; deoxyribonucleic acid; ethylenediamine tetraacetic acid; hemoglobin; intervening sequences; mM; mRNA; mean cell hemoglobin; mean corpuscular hemoglobin concentration; millimolar per liter; ml; pH; power of hydrogen; rpm; untranslated region; μl