Molecular characterization of blood type A, B, and C (AB) in domestic cats and a CMAH genotyping scheme

Abstract

In domestic cats, the AB blood group system consists of the three types A, B, and C (usually called AB), which vary in frequency among breeds and geographic regions. Mismatches cause acute hemolytic transfusion reactions and hemolysis of the newborn due to the presence of naturally occurring anti-A alloantibodies. Cytidine monophosphate-N-acetylneuraminic acid hydroxylase (CMAH) converts N-acetylneuraminic acid (type B) to N-glycolylneuraminic acid (type A), and type C erythrocytes express both antigens. We examined the feline CMAH coding regions and genotyped cats to characterize type A, B, and C animals. Of 421 phenotypically typed cats, 60% were A, 35% B and 5% C. Among the 70 cats for which the CMAH coding region was sequenced, 13 new variants were identified in addition to 16 of the previously reported 18 variants. The CMAH variant c.268T>A is seen in type B cats of most breeds, and the variant c.179G>T results in type B in Turkish breeds. The variants c.1322delT and c.933delA cause frameshifts with early stop codons and thereby type B in some Ragdolls and domestic shorthair cats, respectively. Protein modeling with PROVEAN affirmed their deleterious effects. No type A and C cats had more than one allele with one of the above variants. Variant analysis of three SNVs (c.142G>A, c.268T>A and Δ-53) and blood typing of an additional 351 typed cats showed complete phenotype-genotype concordance. In conclusion, the three CMAH variants c.179G>T, c.268T>A and c.1322delT are the main reasons for the defective NeuGc synthesis causing blood type B in domestic purebred and non-pedigreed cats. Together with the variant c.364C>T for type C in Ragdolls they offer a molecular screening scheme for clinical diagnostics to assure blood type compatibility.

The Prevalence of Blood Groups in Domestic Cats in the Saskatoon and Calgary Areas of Saskatchewan and Alberta, Canada

“…It is proposed that the A and B red blood cell antigens are sialic N-glycolyl-and N-acetylneuraminic acids, respectively (2, 3). Genetic mutations identified in the cytidine monophosphate-N-acetylneuramic acid hydrolase (CMAH) gene have been associated with types A, B and AB, but the specific functional effects of these variations have not yet been determined (4,5).…”

A domestic cat whole exome sequencing resource for trait discovery

“…No other cat in the exome dataset had this variant. Many of the variants associated with cat blood group B and its extended haplotype were detected in one to 11 cats, suggesting five cats as Type B, one was confirmed 59 . Variants were detected in APOBEC3 , which is associated with FIV infection in cats, and three cats had the allelic combination that produces the IRAVP amino acid haplotype that is associated with FIV resistance 60 .…”

Neuigkeiten zur praktischen ABC-Blutgruppen-Bestimmung bei Katzen

“…The major blood group system in domestic cats is known as the feline AB (possibly better referred to as ABC) blood group system with 3 blood types: A, B, and AB (better referred to as C) [1] [2][3] [4]. While overall type A is most common and type C is extremely rare, the frequencies of these three blood types vary among breeds and geographic regions based on many surveys (▶Table 1, ▶ Table 2).…”

“…Of course, these estimates may vary greatly locally and among catteries, because breeding regimes may influence the blood type frequencies. Interestingly, type C is extremely rare except in Ragdolls [4][5] [6] [7] [8], Turkish Angoras, and non-purpose-bred cats in England, Israel, and the Iberian Peninsula (albeit typing methods may have affected some results) [9][10] [11].…”

“…the amino acid (3 bases code for an amino acid) and result in defects in protein/enzyme function and stability. Several of these variants are thought to cause a loss or reduction of the regular CMAH activity needed for the type A antigen and thereby lead to blood type B and C, respectively [4][6][20] [21].…”