1071例地中海贫血基因筛查结果分析

Analysis of thalassemia gene screening in 1071 cases

目的了解来我院就诊的地中海贫血(简称"地贫")筛查患者地贫基因类型并分析平均红细胞体积(MCV)、平均红细胞血红蛋白含量(MCH)在地贫筛查中的应用价值。方法对2015年12月~2016年9月来我院就诊的1071例地贫筛查患者采用裂口PCR(gap-PCR)扩增法检测α地贫基因以及PCR-反向斑点杂交(PCR-RDB)技术检测β地贫基因,血细胞分析仪分析904例患者外周血的MCV、MCH。结果 (1)1071例检测样本中男性556例,检出地贫230例(41.37%);女性515例,检出地贫238例(46.21%),不同性别组检测阳性差异无统计学意义(χ2=2.55,P>0.05)。(2)儿童组(0~16岁)360例,检出地贫174例(48.33%);青壮年组(17~49岁)651例,检出地贫278例(42.7%);老年组(≥50岁)60例,检出地贫16例(26.67%),不同年龄组检测阳性差异有统计学意义(χ2=10.48,P<0.01)。(3)1071例样本共检测α地贫293例(27.36%),其中以αα/--SEA、-α3.7/αα、αα/-α4.2基因型为主,占α地贫的93.86%;检测β地贫157例(14.66%),其中以CD41-42、IVS-Ⅱ-654、-28、CD71-72、CD17基因型为主,占β地贫的82.81%;α地贫复合β地贫18例,比例为1.68%。(4)MCV用于α地贫、β地贫和αβ复合型地贫的筛查的灵敏度分别为91.18%、99.21%、92.31%,特异度为54.18%;MCH用于α地贫组、β地贫组和αβ复合型地贫组的筛查的灵敏度分别为94.12%、99.21%、100.00%,特异度为51.90%;MCV+MCH用于α地贫组、β地贫组和αβ复合型地贫组的筛查的灵敏度分别为89.08%、99.21%、84.62%,特异度为49.24%;MCV与MCH的灵敏度差异无统计学意义(χ~2=1.77,P>0.05),特异度差异无统计学意义(χ~2=0.55,P>0.05)。结论 1071例地贫患者中α地贫中以αα/--SEA基因型最为常见,β地贫中以βCD41-42基因型最为常见,在地贫筛查中,MCV+MCH用于筛查效果好。

Objective To investigate the genetic heterogeneity of thalassemin of patients in our hospital and the diagnostic value of mean corpuscular volume（MCV） and mean corpuscular hemoglobin （MCH）in thalassemia screening.Methods From December 2015 to September 2016,1071 patients with thalassemia in our hospital were selected,gap-PCR and polymerase chain reaction-reverse dot blot （PCR-RDB） were used to test α-thalassemia gene and -thalassemia gene,hematology analyzer was used to test mean corpuscular volume （MCV） and mean corpuscular hemoglobin （MCH） of 904 patients.Results （1）Among the 1071 cases,556 cases was male and 515 cases was female,the positive rate of thalassemia was 41.37%（230 cases） for male and 46.21%（238 cases） for female,which was displayed no statistical differences in the two groups （x2=2.55,P〉0.05）.（2）During different group such as children group （0-16 years old, 360 cases）,aduh group （17-49 years old,651 cases） and senior group （≥ 50 years old,60 cases）,the positive rate of thalassemia was 48.33%（174 cases）,42.7%（278 cases） and 26.67%（16 cases）,respectively,which was displayed statistical differences among the groups （x2=10.48,P〈0.01）.（3）among 1071specimens,293 cases （27.36%） were diagnosed as α-thalassemia and 157 cases （14.66%） were diagnosed as β-thalassemia.Among the α-thalassemia genotypes,αα--SEA,- α3.7/αα,αα/-α4.2 were the most common genotypes （93.86%）;among the β-thalassemia genotypes,CD41-42,IVS- 11 -654,-28,CD71-72,CD17 were the most common genotypes （82.81%）;18 cases （1.68%） were diagnosed as α- thalassemia combined with β-thalassemia.（4）The diagnostic sensitivity of MCV for α-thalassemia, β-thalassemi- a and αβ-thalassemia screening were 91.18%,99.21% and 92.31%,respectively,and 54.18% for the diagnostic specificity. The diagnostic sensitivity of MCH for α-thalassemia,β-thalassemia and αβ-thalassemia screening were 94.12%, 99.21% and 100.00%,respectively,and 51.90% for the diagnostic specificity.The diagnostic sensitivity of MCV＋MCH for α-thalassemia,β-thalassemia and αβ-thalassemia screening were 89.08% ,99.21% and 84.62% ,respectively,and 49.24%% for the diagnostic specificity.There was no significant difference in the sensitivity and specificity between MCV and MCH （x2=1.77,P〉0.05;x2=0.55,P〉0.05）.Conclusion αα-SEA genotype and βCD41-42 genotype are the most common type in α-thalassemia and β-thalassemia in 1071 patients with thalassemia,it is reasonable to screening the thalassemia by MCV combine with MCH. [Key words]α-thalassemia;β-thalassemia;Mean corpuscular volume;Mean corpuscular hemoglobin