title: Genetic origin of α0-thalassemia (SEA deletion) in Southeast Asian populations and application to accurate prenatal diagnosis of Hb Bart's hydrops fetalis syndrome.
abstract: α0-thalassemia of SEA deletion (-SEA) is common among Southeast Asian and Chinese. Using haplotype and phylogenetic analyses, we examined the origin of this defect in Southeast Asian populations. Study was done on both normal and α0-thalassemia alleles in 3 ethnic groups including 96 Thai, 52 Laotian and 21 Cambodian. Five SNPs encompassing the (-SEA) including (rs3760053 T>G), (rs1211375 A>C), (rs3918352 A>G), (rs1203974 A>G) and (rs11248914 C>T) were examined using high-resolution melting assays. It was found that 94.0% of Thai, 100% of Laotian and 100% of Cambodian α0-thalassemia alleles were linked to the same haplotype: the haplotype H4 (AAGC), representing an Asian specific origin. An G allele of the (rs3760053) was found to be in strong linkage disequilibrium with the α0-thalassemia allele in these populations. A multiplex PCR assay was developed to detect simultaneously the (-SEA) allele and genotyping of a linked (rs3760053) to improve accuracy of prenatal diagnosis of α0-thalassemia. Application of this multiplex PCR assay for routine prenatal diagnosis of α0-thalassemia in 12 families revealed a 100% concordant result with conventional gap-PCR assay. Therefore, a single genetic origin is responsible for the spread and high prevalence of the (-SEA) in the region. The multiplex PCR assay developed should provide a double-check PCR system for more accurate diagnosis and allow the monitoring of possible maternal contamination at prenatal diagnosis of this important genetic disorder.
authors.affiliation: Biomedical Science Program, Graduate School, Khon Kaen University, Khon Kaen, Thailand.|Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Wittaya
authors.initials: W
authors.lastname: Jomoui
authors.affiliation: Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Goonnapa
authors.initials: G
authors.lastname: Fucharoen
authors.affiliation: Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Kanokwan
authors.initials: K
authors.lastname: Sanchaisuriya
authors.affiliation: Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Patnaree
authors.initials: P
authors.lastname: Charoenwijitkul
authors.affiliation: Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Jitpanu
authors.initials: J
authors.lastname: Maneesarn
authors.affiliation: Department of Medical Genetics, School of Basic Medical Sciences, Southern Medical University, Guangdong, China.
authors.forename: Xiangmin
authors.initials: X
authors.lastname: Xu
authors.affiliation: Centre for Research and Development of Medical Diagnostic Laboratories, Faculty of Associated Medical Sciences, Khon Kaen University, Khon Kaen, Thailand.
authors.forename: Supan
authors.initials: S
authors.lastname: Fucharoen
mesh_terms: D001210:Asia, Southeastern / Q000453:epidemiology; D005260:Female; D006580:Genetic Carrier Screening; D005838:Genotype; D006455:Hemoglobins, Abnormal / Q000235:genetics*; D006801:Humans; D015160:Hydrops Fetalis / Q000175:diagnosis* / Q000453:epidemiology / Q000235:genetics; D060885:Multiplex Polymerase Chain Reaction; D010802:Phylogeny; D011247:Pregnancy; D011296:Prenatal Diagnosis / Q000379:methods*; D017384:Sequence Deletion; D017085:alpha-Thalassemia / Q000175:diagnosis* / Q000453:epidemiology / Q000235:genetics
chemical_list: D006455:Hemoglobins, Abnormal; C030448:hemoglobin Bart's