Esteghamat Fatemehsadat, Imanian Hashem, Azarkeivan Azita, Pourfarzad Farzin, Almadani Navid, Najmabadi Hossein
Kariminejad-Najmabadi Pathology and Genetics Center, Tehran, Iran.
Hemoglobin. 2007;31(4):463-9. doi: 10.1080/03630260701641286.
Deltabeta-thalassemia (thal) is a disorder, characterized by increased levels of fetal hemoglobin (Hb F) in adult life. A considerable number of deletions of variable size and position in the beta-globin gene cluster are associated with the clinical manifestation of deltabeta-thal. In this study we have determined the presence of the eight most common deletions in Iranian patients. Thirty-two patients from 19 families were referred to the Kariminejad-Najmabadi Pathology and Genetics Center, Tehran, Iran (a private genetics center), within the past 3 years with elevated levels of Hb F and low mean corpuscular volume (MCV). After obtaining their informed consent, DNA was extracted from whole blood by the salting-out method. Detection of eight deletions was performed using polymerase chain reaction (PCR). These deletions included the hereditary persistence of fetal Hb (HPFH) 1 (Black) and 3 (Indian), Spanish (-114 kb), Sicilian (-13,377 bp), Chinese (G)gamma((A)gammadeltabeta)(0)-thal (-100 kb), Asian-Indian inversion-deletion (G)gamma((A)gammadeltabeta)(0)-thal, and the Turkish form of inversion-deletion (deltabeta)(0)-thal, as well as the Hbs Lepore, which are characterized by unequal crossovers between the delta- and beta-globin genes. We found the Sicilian (-13,377 bp) and Hb Lepore deletions as well as the Asian-Indian (G)gamma((A)gammadeltabeta)(0)-thal in 11 (57.89%), three (15.78%) and five (26.31%) families, respectively. None of the aforementioned deletions were found in one of the patients. This is the first study of the deletions involved in deltabeta-thal in Iranian patients. Our study highlights the importance of detecting these mutations for prenatal diagnosis carrier detection and genotype/phenotype prediction.
δβ地中海贫血是一种在成年期以胎儿血红蛋白(Hb F)水平升高为特征的疾病。β珠蛋白基因簇中大量大小和位置各异的缺失与δβ地中海贫血的临床表现相关。在本研究中,我们确定了伊朗患者中八种最常见缺失的存在情况。在过去3年里,来自19个家庭的32名患者因Hb F水平升高和平均红细胞体积(MCV)降低被转诊至伊朗德黑兰的卡里米内贾德 - 纳杰马巴迪病理与遗传学中心(一家私立遗传学中心)。在获得他们的知情同意后,采用盐析法从全血中提取DNA。使用聚合酶链反应(PCR)检测八种缺失。这些缺失包括胎儿血红蛋白遗传性持续存在(HPFH)1型(黑人型)和3型(印度型)、西班牙型(-114 kb)、西西里型(-13,377 bp)、中国型(G)γ((A)γδβ)0 - 地中海贫血(-100 kb)、亚洲 - 印度型倒位缺失(G)γ((A)γδβ)0 - 地中海贫血以及土耳其型倒位缺失(δβ)0 - 地中海贫血,还有以δ和β珠蛋白基因之间不等交换为特征的血红蛋白Lepore。我们分别在11个(57.89%)、3个(15.78%)和5个(26.31%)家庭中发现了西西里型(-13,377 bp)、血红蛋白Lepore缺失以及亚洲 - 印度型(G)γ((A)γδβ)0 - 地中海贫血。在其中一名患者中未发现上述任何一种缺失。这是对伊朗患者中涉及δβ地中海贫血的缺失情况的首次研究。我们研究强调了检测这些突变对于产前诊断、携带者检测以及基因型/表型预测的重要性。