罕见Hb Hekinan合并东南亚型α-地中海贫血家系分析

Diagnosis in a family carrying the rare Hb Hekinan compound with Southeast Asian deletion

目的 鉴定罕见α-地中海贫血HBA1:c.84G>T突变引起Hb Hekinan患者并进行家系分析。方法 采集家系成员外周血进行血细胞分析及毛细管电泳血红蛋白分析,同时采用缺口PCR(Gap-PCR)、反向点杂交法(RDB)和Sanger测序法进行α-地中海贫血基因检测。结果 先证者α-地中海贫血HBA1:c.84G>T突变合并东南亚型缺失,父亲为HBA1:c.84G>T杂合子突变,母亲及其妹妹为东南亚型α-地中海贫血杂合缺失。结论 鉴定了中国人群中罕见α-地中海贫血HBA1:c.84G>T基因突变,丰富了中国人群中罕见α-地中海贫血基因库,当血液学表型与常见基因型不符时,应进一步做罕见基因型的检测以避免漏诊或误诊,这有助于指导临床诊断和遗传咨询。

Objective The aim of this study was to identify the rare thalassemia genotype in a family and perform pedigree analysis. Methods Peripheral blood was collected from the family members for hematology analysis and high-performance liquid chromatography(HPLC). Then gap-polymerase chain reaction(gap-PCR), reverse dot-blot and Sanger sequencing were used for thalassemia genetic analysis. Results A heterozygous HBA1 mutations c.84G>T compound with the--SEA(Southeast Asian) deletion, were revealed in the proband. A heterozygous mutation, HBA1:c.84G>T was identified in the proband’s father. Proband’s mother and sister were--SEA(Southeast Asian) deletion. Conclusion We had identified a rare thalassemia mutation(HBA1:c.84G>T) in a Chinese family and enriched the rare α-thal gene pool in the Chinese population.When abnormal hemoglobin or hemoglobin peak is found, further investigation of rare genotypes should be conducted to avoid missed diagnosis or misdiagnosis, which can help guide clinical diagnosis, population screening and genetic counseling.