Caruccio Lorraine, Walkovich Kelly, Bettinotti Maria, Schuller Randy, Stroncek David
Department of Transfusion Medicine, Warren G Magnuson Clinical Center, National Institutes of Health, Bethesda, MD 20892, USA.
Transfusion. 2004 Jan;44(1):77-82. doi: 10.1046/j.0041-1132.2004.00606.x.
Human neutrophil antigen-2a (NB1) is located on NB1 glycoprotein, which is expressed on subpopulations of neutrophils. PRV-1 is a gene that is over-expressed in neutrophils from patients with polycythemia rubra vera. The gene encoding NB1 differs from PRV-1 at four nucleotides. The purpose of this study was to determine if PRV-1 and NB1 are alleles of the same gene or two separate genes; and, moreover, if they are alleles, to explore potential correlations to NB1 glycoprotein expression.
Primer pairs were used to amplify WBC DNA in the regions surrounding the four NB1 polymorphic sites. The four resulting amplicons were sequenced. The size of the neutrophil population in each donor that stained brightly with CD177 antibody was assessed by flow cytometry.
If PRV-1 and NB1 are separate genes, then all people should be heterozygous for the PRV-1/NB1 polymorphisms. Because 11 of 23 donors were homozygous for PRV-1 polymorphisms at all four sites, PRV-1 and NB1 are alleles of the same gene, CD177. When the sequenced exons were compared with PRV-1, 13 single nucleotide polymorphisms (SNPs) that result in amino acid changes were found. The G42C NB1 polymorphism, found in 10 donors, was the most common SNP. The size of the CD177 bright-staining neutrophil population was greater in 42C/C donors than in 42G/G donors (66 +/- 20% vs. 41 +/- 21%, p = 0.004).
PRV-1 and NB1 are alleles of the polymorphic gene CD177. The most common SNP in bp 42 predicted an amino acid change that may have an effect on protein expression.
人类中性粒细胞抗原2a（NB1）位于NB1糖蛋白上，该糖蛋白在中性粒细胞亚群中表达。PRV-1是一个在真性红细胞增多症患者的中性粒细胞中过度表达的基因。编码NB1的基因在四个核苷酸上与PRV-1不同。本研究的目的是确定PRV-1和NB1是同一基因的等位基因还是两个不同的基因；此外，如果它们是等位基因，探讨与NB1糖蛋白表达的潜在相关性。
使用引物对扩增四个NB1多态性位点周围区域的白细胞DNA。对产生的四个扩增子进行测序。通过流式细胞术评估每个供体中用CD177抗体染色明亮的中性粒细胞群体的大小。
如果PRV-1和NB1是不同的基因，那么所有人在PRV-1/NB1多态性方面都应该是杂合子。因为23名供体中有11名在所有四个位点的PRV-1多态性上是纯合子，所以PRV-1和NB1是同一基因CD177的等位基因。当将测序的外显子与PRV-1进行比较时，发现了13个导致氨基酸变化的单核苷酸多态性（SNP）。在10名供体中发现的G42C NB1多态性是最常见的SNP。42C/C供体中CD177染色明亮的中性粒细胞群体大小大于42G/G供体（66±20%对41±21%，p = 0.004）。
PRV-1和NB1是多态性基因CD177的等位基因。42位碱基处最常见的SNP预测了一个可能影响蛋白质表达的氨基酸变化。
