ISBT 010 Gene Location and Antigens

Study Notes

The Diego System (ISBT 010)

Located on Chromosome 17q
22 antigens, with 3 sets of antithetical antigens (Dia/Dib, Wra/Wrb, and Wu/DISK)
Low incidence of antigens Wda, Rba, and WARR
Antigens are located on band 3 protein (anion exchanger/AE-1)
Involved in gas transport and acid-base equilibrium
Dia antigen has served as a useful tool in anthropologic studies of Mongolian ancestry
Associated with southeast Asian ovalocytosis
Antigens are expressed on newborns
Resistant to treatment with ficin, papain, DTT, and glycine-acid EDTA
Bpa-sensitive to papain
Can cause Hemolytic Transfusion Reaction (HTR) and Hemolytic Disease of the Fetus and Newborn (HDFN)

The YT System (ISBT 011)

Located on Chromosome 7q
Two antigens: Yta (high prevalence) and Ytb (low prevalence)
Yta is present in all populations, while Ytb is found in about 8% of whites and 21-26% of Israelis, but not in Japanese
Antigens are variably sensitive to ficin and papain, sensitive to DTT, and resistant to glycine-acid EDTA treatment
Involved in neurotransmission through erythrocyte acetylcholinesterase

The XG System (ISBT 012)

Located on the short arm of the X chromosome
Higher prevalence in females than males
Xga is present in 66% of males and 89% of females
Xg(a+) individuals have a high expression of CD99 on their RBCs, while Xg(a-) females have a low expression
68% of Xg(a-) males have a high expression and 32% have a low expression of CD99
Sensitive to ficin and papain but resistant to DTT treatment

The Sciana System (ISBT 013)

Located on Chromosome 1p
Three antigens: Sc1 (high prevalence), Sc2 (low prevalence), and Sc3 (high prevalence)
Sc1 and Sc2 are resistant to ficin and papain, and all three antigens are resistant to DTT treatment, except for Sc2
Product of the gene is an erythroid membrane-associated protein (ERMAP), an RBC adhesion protein

The Dombrock System (ISBT 014)

Located on Chromosome 12p
Antigens are carried on a mono-ADP ribosyltransferase 4 (ART4) attached to the RBC membrane by a GPI anchor
Total absence of DO expression is observed in paroxysmal nocturnal hemoglobinuria III RBCs
Antigens are resistant to ficin, papain, and glycine-acid EDTA, and sensitive to 0.2 M DTT treatment
Doa and Dob are poor immunogens, while Gya is highly immunogenic
Anti-Doa and anti-Dob IgG have caused delayed HTRs but no clinical HDFN

The Colton System

Located on Chromosome 7p
Three antigens: Coa (high prevalence), Cob (low prevalence), and Co3 (formerly COab)
Co3 is present in all RBCs except Co(a-b-) phenotype
Antigens are carried on an integral membrane protein, aquaporin 1 (AQP1), which accounts for 80% of water reabsorption in the kidneys
Expressed on RBCs of newborns
Resistant to treatment with ficin, papain, chloroquine, and DTT

Description

This quiz covers the location and characteristics of the ISBT 010 gene, including its history, antigens, and functions. It also touches on the gene's association with certain medical conditions and its use in anthropologic studies.