title: Delineation of the molecular basis of borderline hemoglobin A2 in Chinese individuals.
abstract: BACKGROUND
  The "gray zone" of borderline hemoglobin A2 (Hb A2) may be present in a large section of the population, especially in countries where thalassemia is common. However, very little is currently known of the molecular basis of borderline Hb A2 in Chinese individuals.
  
  
  METHODS
  In this study, we performed a comprehensive analysis of the globin genotypes and KLF1 gene mutations associated with borderline Hb A2 in 165 Chinese subjects.
  
  
  RESULTS
  Fifteen (9.1%) were positive for a molecular defect in the α-,β-globin genes, of whom, α-thalassemia mutations and α-globin gene triplication were found in eleven cases, accounting for about 73.3% of these globin gene defects. Twenty (12.1%) were positive for a molecular defect in the KLF1 gene. Eight different mutations were identified, six of which are here reported for the first time. The most common is the G176AfsX179 mutation, accounting for 50% of the total.
  
  
  CONCLUSIONS
  The molecular characterization of borderline Hb A2 in Chinese individuals is significantly different than in Italian population. Our data is conductive to provision of genetic counseling for Chinese individuals with borderline Hb A2.
authors.affiliation: Prenatal Diagnostic Center, Dongguan Maternal & Children Health Hospital, Dongguan, Guangdong Province, People's Republic of China.
authors.forename: Ji-Wu
authors.initials: JW
authors.lastname: Lou
authors.affiliation: Prenatal Diagnostic Center, Guangzhou Women & Children Medical Center, Guangzhou Medical College, Guangzhou, Guangdong Province, People's Republic of China.
authors.forename: Dong-Zhi
authors.initials: DZ
authors.lastname: Li
authors.affiliation: Department of Medical Genetics, School of Basic Medical Sciences, Southern Medical University, Guangzhou, Guangdong Province, People's Republic of China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Prenatal Diagnostic Center, Dongguan Maternal & Children Health Hospital, Dongguan, Guangdong Province, People's Republic of China.
authors.forename: Yi
authors.initials: Y
authors.lastname: He
authors.affiliation: Prenatal Diagnostic Center, Dongguan Maternal & Children Health Hospital, Dongguan, Guangdong Province, People's Republic of China.
authors.forename: Man-Na
authors.initials: MN
authors.lastname: Sun
authors.affiliation: Prenatal Diagnostic Center, Dongguan Maternal & Children Health Hospital, Dongguan, Guangdong Province, People's Republic of China.
authors.forename: Wan-Ling
authors.initials: WL
authors.lastname: Ye
authors.affiliation: Prenatal Diagnostic Center, Dongguan Maternal & Children Health Hospital, Dongguan, Guangdong Province, People's Republic of China. Electronic address: liuliang71215@163.com.
authors.forename: Yan-Hui
authors.initials: YH
authors.lastname: Liu
mesh_terms: D044466:Asian People; D001483:Base Sequence; D005817:Genetic Counseling; D005820:Genetic Testing; D005838:Genotype; D006443:Hemoglobin A2 / Q000235:genetics*; D006801:Humans; D051741:Kruppel-Like Transcription Factors / Q000235:genetics*; D008969:Molecular Sequence Data; D009154:Mutation; D055542:alpha-Globins / Q000235:genetics*; D017085:alpha-Thalassemia / Q000208:ethnology / Q000235:genetics*; D055544:beta-Globins / Q000235:genetics*; D017086:beta-Thalassemia / Q000208:ethnology / Q000235:genetics*
chemical_list: D051741:Kruppel-Like Transcription Factors; D055542:alpha-Globins; D055544:beta-Globins; C080774:erythroid Kruppel-like factor; D006443:Hemoglobin A2
keywords: Borderline Hb A2; Globin gene; KLF1; Thalassemia