Ruengdit Chedtapak, Khamphikham Pinyaphat, Jinorose Nathawat, Pornprasert Sakorn
Division of Clinical Microscopy, Department of Medical Technology, Faculty of Associated Medical Sciences, Chiang Mai University, Chiang Mai, Thailand.
Department of Medical Laboratory, Phayao Hospital, Phayao, Thailand.
Hemoglobin. 2021 Mar;45(2):75-79. doi: 10.1080/03630269.2021.1906269. Epub 2021 Apr 6.
α-Thalassemia (α-thal) Chiang Rai (- -; NC_000016.10: g.144215_188843del) was identified as a novel 44.6 kb deletional type of α-thalassemia (α-thal), removing all α-like globin genes. However, little is known about the deleterious effects of this genetic disorder, particularly when it is combined with other types of thalassemia. We performed molecular analysis of the - - deletion using gap-polymerase chain reaction (gap-PCR) in two independent families residing in Phayao and Chiang Mai, Thailand, with an unknown causative mutation for Hb Bart's hydrops fetalis syndrome and Hb H disease. Five out of seven individuals were diagnosed to be heterozygous for the - - deletion. Of these, two also carried Hb H disease with compound heterozygosities for - - and -α (rightward) deletions. However, hematological parameters of the - - carriers displayed microcytic hypochromic anemia that is comparable to other α-thal traits. Although the prevalence of - - has never been elucidated in a specific population, our study demonstrated that genotyping for - - might be considered as an additional investigation for unexplained Hb Bart's hydrops fetal syndrome and Hb H disease.
α地中海贫血（α-thal）清莱型（--；NC_000016.10: g.144215_188843del）被鉴定为一种新型的44.6 kb缺失型α地中海贫血（α-thal），它删除了所有α样珠蛋白基因。然而，对于这种遗传疾病的有害影响知之甚少，尤其是当它与其他类型的地中海贫血合并时。我们使用缺口聚合酶链反应（gap-PCR）对泰国清莱府和清迈府两个独立家庭中的--缺失进行了分子分析，这两个家庭患有Hb Bart水肿胎儿综合征和Hb H病，但致病突变不明。七名个体中有五名被诊断为--缺失杂合子。其中，两名还携带Hb H病，为--和-α（右向）缺失的复合杂合子。然而，--携带者的血液学参数显示为小细胞低色素性贫血，与其他α地中海贫血特征相当。尽管尚未在特定人群中阐明--的患病率，但我们的研究表明，对于不明原因的Hb Bart水肿胎儿综合征和Hb H病，--基因分型可作为一项额外的调查手段。
