Weak expression of antigen caused by the variation in the regulatory region of ABO allele and cause analysis

doi:10.3969/j.issn.1673-8640.2021.06.013

Abstract

Abstract:

Objective To analyze the reason of 1 case of the discrepancy of ABO blood group and find out the mutation gene through carrying out genotyping. Methods Serologic blood group was identified by microcolumn gel method,and antibodies were screened and determined with DG GelConfirm cards,DG GelNeutral cards,DG GelCoombs cards. The enhancer,promoter,exon 1-exon 7 and their adjacent intron region of ABO gene were amplified by polymerase chain reaction（PCR）,the PCR products were directly sequenced to identify the gene mutation. Results The patient's red blood cells showed weak agglutination with anti-A（++）,noagglutination with anti-B. The patient's serum showed strong agglutination with A1 cell（++++）,B cell（++++）,noagglutination with O cells（A_weak）. The direct antiglobulin test,indirect antiglobulin test and antibody screening were all negative. Totally,4 short 43 bp tandem repeat units in enhancer region was 3 more than the normal A allele. Conclusions The 4 short 43 bp tandem repeat units in enhancer region of A allele is the cause of the weak expression of A antigen.

Key words: ABO blood group, Genotype, Regulatory region, Enhancer

CLC Number:

R446.1

GU Yuwei, WANG Chengyun, GU Ping, PAN Qiuhui, WANG Jing, CHEN Guangjie. Weak expression of antigen caused by the variation in the regulatory region of ABO allele and cause analysis[J]. Laboratory Medicine, 2021, 36(6): 637-641.

Figures/Tables 5

References 14

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引物名称	引物序列（5'→3'）	扩增片段长度/bp
Promoter-E1^①	F：CGGGAGACAGGGTGTCAAG	731
	R：TCGGGCGGTAGGTGCTGAA
Enhancer	F：CCCCATCCATAGTCAGATAAGC	724
	R：AAAGCAGCCAGCCAGTGTT
ABO-E2	F：GAGAAGGAGGGTGAGTGATG	323
	R：AGTGAGATGAGCCTGTTGC
ABO-E3	F：GTCCCAGAACCAAGAGTGA	616
	R：TCCAGAGGTATCCAGGTGA
ABO-E4	F：AAGACCAACATCCCAAGAA	624
	R：GAGCCACAGGAGGAAAGAG
ABO-E5	F：TGCTTACCTGCATCCCACGCT	572
	R：TCAAGGAAACCGCCCTCTAAT
ABO-E6	F：CATTTGCCTCTGGTTGGTTT	522
	R：CTGGAGAAGGAGCTGGGTTT
ABO-E7	F：TCTGCTGCTCTAAGCCTTCC	878
	R：CCCGTTCTGCTAAAACCAAG

引物名称	引物序列（5'→3'）	扩增片段长度/bp
Promoter-E1^①	F：CGGGAGACAGGGTGTCAAG	731
	R：TCGGGCGGTAGGTGCTGAA
Enhancer	F：CCCCATCCATAGTCAGATAAGC	724
	R：AAAGCAGCCAGCCAGTGTT
ABO-E2	F：GAGAAGGAGGGTGAGTGATG	323
	R：AGTGAGATGAGCCTGTTGC
ABO-E3	F：GTCCCAGAACCAAGAGTGA	616
	R：TCCAGAGGTATCCAGGTGA
ABO-E4	F：AAGACCAACATCCCAAGAA	624
	R：GAGCCACAGGAGGAAAGAG
ABO-E5	F：TGCTTACCTGCATCCCACGCT	572
	R：TCAAGGAAACCGCCCTCTAAT
ABO-E6	F：CATTTGCCTCTGGTTGGTTT	522
	R：CTGGAGAAGGAGCTGGGTTT
ABO-E7	F：TCTGCTGCTCTAAGCCTTCC	878
	R：CCCGTTCTGCTAAAACCAAG

样本来源	抗A抗体	抗B抗体	抗H抗体	A1细胞	B细胞	O细胞	直接抗人球蛋白试验	间接抗人球蛋白试验	抗体筛查试验
患儿	++	-	++	++++	++++	-	-	-	-
患儿父	++++	-	+	-	++++	-	-	-	-
患儿母	-	++++	+	++++	-	-	-	-	-

样本来源	抗A抗体	抗B抗体	抗H抗体	A1细胞	B细胞	O细胞	直接抗人球蛋白试验	间接抗人球蛋白试验	抗体筛查试验
患儿	++	-	++	++++	++++	-	-	-	-
患儿父	++++	-	+	-	++++	-	-	-	-
患儿母	-	++++	+	++++	-	-	-	-	-

样本来源	第1~7号外显子突变位点	调控区变异	基因型
患儿	106G>T,188G>A,189C>T,261delG,297A>G	CBF/NF-Y微卫星区有4个43 bp串联,其中第1个43 bp重复序列中的第nt41位为C,另外3个43 bp重复序列的第nt41位均为G	—
患儿父	261delG,467C>T	无变异	A102/O01
患儿母	106G>T,188G>A,189C>T,220C>T,261delG,297A>G,526C>G,646T>A,657C>T681G>A,703G>A,771C>T,796C>A,803G>C,829G>A,930G>A,1096G>A	无变异	B101/O02