The Augustine blood group system, 48 years in the making

Area of Science:

• Hematology
• Genetics
• Immunology

Background:

• The Ata antigen, identified in 1967, was later classified as AUG1 within the Augustine (AUG) blood group system in 2015.
• The Augustine blood group system was established following the identification of the gene encoding Ata and a null phenotype (AUG:–1,–2).

Purpose of the Study:

• To detail the genetic basis and clinical significance of the Augustine (AUG) blood group system.
• To characterize the rare At(a–) phenotype and its associated genetic mutations.

Main Methods:

• Identification of the gene encoding the Ata antigen (SLC29A1).
• Characterization of genetic mutations leading to At(a–) and AUGnull phenotypes.
• Analysis of antibody reactions and clinical implications, including transfusion reactions.

Main Results:

• The Augustine gene, SLC29A1, encodes the equilibrative nucleoside transporter ENT1.
• The At(a–) phenotype (AUG:–1,2) results from homozygosity for c.1171G>A (Glu391Lys).
• The AUGnull phenotype (AUG:–1,–2) results from homozygosity for a splice site mutation (c.589+1G>C) in a specific family, potentially linked to pseudogout and abnormal bone calcification.

Conclusions:

• The Augustine blood group system is defined by the SLC29A1 gene, with specific mutations causing rare phenotypes.
• Anti-Ata antibodies can cause hemolytic transfusion reactions.
• The null phenotype in one family may have associated systemic health implications beyond hematology.