ABO is the most important blood group system for transfusion and solid organ transplantation, but it is only over the past 15 years that the techniques for studying its molecular basis became mainstream. Many of its common and rare alleles are now well characterized and by using various expression systems, their effects on the resulting glycosyltransferases are being appreciated. As progress has been made in genetics and glycobiology, so too do reagents used to routinely type red blood cells in the clinical laboratory evolve. Monoclonal reagents are now widely used. This has created difficulties in nomenclature to describe subtype phenotypes as the names of some of these uncommon phenotypes were based on the red blood cell agglutination pattern using polyclonal reagents. In this brief review a discussion of the wild-type ABO allele and the enzymes it encodes is followed by a description of a selection of unusual and fascinating alleles-some that encode enzymes that create both A and B antigens and others that result from hybridization events. A short section on the techniques of ABO allele investigation describes some of the current methodologies used in both research and clinical laboratories.

中文翻译：

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2个核苷酸的区别是什么：ABO遗传学的简短回顾。

ABO是输血和实体器官移植最重要的血型系统，但是直到最近15年，研究其分子基础的技术才成为主流。现在已经很好地表征了其许多常见和稀有等位基因，并且通过使用各种表达系统，人们认识到它们对所得糖基转移酶的作用。随着遗传学和糖生物学的发展，临床实验室中用于常规分型红细胞的试剂也在不断发展。单克隆试剂现已广泛使用。这给描述亚型表型带来了命名上的困难，因为其中一些罕见表型的名称基于使用多克隆试剂的红细胞凝集模式。在这篇简短的综述中，对野生型ABO等位基因及其编码的酶进行了讨论，随后介绍了一些不寻常且引人入胜的等位基因-一些编码产生A和B抗原的酶，以及其他由杂交事件产生的酶。关于ABO等位基因研究技术的一小部分描述了研究和临床实验室中使用的一些当前方法。