ERIK, a low‐frequency red cell antigen of the MNS blood group system associated with Sta

Abstract

A new low-frequency red cell antigen, ERIK (MNS37), is associated with the Sta antigen of the MNS system. Four ERIK+ propositi have been identified: all are St(a+). Thirteen other St(a+) samples, including one of the Mz type, and over 200 St(a-) samples were ERIK-. In two of the propositi ERIK is associated with an abnormal trypsin-resistant M antigen; in the others it is associated with N, which is shown to be expressed weakly in one family. Immunoblotting with an antibody to an epitope common to glycophorin A (GPA) and glycophorin B (GPB) gave identical results with St(a+) ERIK+ and St(a+) ERIK- cells, revealing GPA, GPB, an abnormal structure GPSta and aggregates of these components. In the propositi with trypsin-resistant M, GPSta carries the unusual M antigen, whereas in the M-N+ERIK+ individual analysed by immunoblotting GPSta carries N. Immunoblotting with anti-Sta and anti-ERIK showed that Sta is located on GPSta but that ERIK is located on GPA, presumably the GPA molecule encoded by the GYPA gene contiguous to the gene encoding GPSta.

A novel Sta glycophorin produced via gene conversion of pseudoexon III from glycophorin E to glycophorin A gene

“…It should also be noted that except for the novel 6.5kb band, there was no gross alteration in either the GPB or GPE gene. This observation is consistent with the results of family studies indicating the proband to be a heterozygote of the GPSt a gene [Daniels et al, 1993].…”

“…The incidence documented so far for the various St a isoforms differs significantly between Asians and Africans or Caucasians [Race and Sanger, 1975;Rearden et al, 1990;Dahr et al, 1990;Huang and Blumenfeld, 1991b;Lomas et al, 1992;Daniels et al, 1993;Huang et al, 1994;Shih et al, 2000]. Taken together, it appears that the multiple alleles of GPSt a have arisen independently in selected segments of the human population.…”

“…His erythrocytes typed M+N+(weak)S+s-St(a+)ERIK+. A detailed family study, including serologic investigation and Western blot analysis, had been described [Daniels et al, 1993]. Western blots of glycophorins showed the expression of GPA, GPB and GPSt a .…”

MNS Blood Group System

“…Anti -ERIK is present in the serum of the wife of the Danish St(a + ) ERIK + propositus and caused a positive DAT on the red cells of their baby [387] . Anti -ERIK is also present in two multispecifi c sera containing numerous antibodies to low frequency antigens [387] .…”

ISBT Working Party on Terminology for Red Cell Surface Antigens

“…It is envisaged that a full revision of the ISBT terminology will be published following the Amsterdam meeting in 1994. defined by antibodies which generally behave as insep arable anti-MNS10 and anti-MNS19 (anti-Mur/Hut), although there are some exceptional phenotypes [5], MNS36 (SAT) is associated with a unique GP(A-B) hy brid in one family and an abnormal M antigen in another [6]. MNS37 (ERIK) is located on a GPA molecule with a Gly59->Arg substitution; exon skipping within the abnor mal GYPA gene also results in a shortened GPA molecule expressing MNS15 (Sta) [7,8]. 004, The Rh System.…”