A novel FY allele in Brazilians

Abstract

The GATA box single nucleotide polymorphism (SNP) at position -33 (T>C) in Blacks silences the expression of FY*B in erythrocytes, and the substitution 265 C>T, together with 298 G>A, weakens the Fy(b) antigen (Fy(x)). Individuals with these phenotypes/genotypes who receive Fy(b+) blood are unlikely to be alloimmunized to Fy(b) because, in the presence of 265 T, the Fy(b) antigen is expressed, and in the case of -33 C, other tissues express Duffy protein and probably the Fy(b) antigen. We studied samples from 361 blood donors (182 of African ancestry and 179 of Caucasian ancestry) by haemagglutination and polymerase chain reaction (PCR) restriction fragment length polymorphism (RFLP). Forty Caucasian and 130 donors of African ancestry were serologically Fy(b-); among these, the majority of the donors of African ancestry had FY*B with the GATA SNP, while the majority of Caucasians typing Fy(b-) had FY*B with 265 T/298 A SNPs. Six of the Fy(b-) donors (three Africans and three Caucasians) had both GATA and 265/298 SNPs, and six donors of Caucasian ancestry apparently had a GATA SNP. Samples from two donors - one African and one Caucasian with an unusual MspA1I-RFLP pattern - were sequenced and found to have a novel SNP (145 G>T) co-existent with 265 C>T and 298 G>A SNPs. These findings highlight the importance of establishing the incidence and nature of molecular events that impact on Duffy expression in different populations.

Association of Duffy Blood Group Gene Polymorphisms with IL8 Gene in Chronic Periodontitis

“…The FY polymorphisms, including the SNPs 125 G>A ( FY*01/FY*02 ), 265 C>T, 298 G>A ( FY*02M.01 ) and the GATA-1 box mutation −67T>C ( FY*02N.01 ), were determined by polymerase chain reaction–restriction fragment length polymorphism (PCR–RFLP), as previously described by Castilho et al [23], and described in the Table 1. …”

Duffy Negative Antigen Is No Longer a Barrier to Plasmodium vivax – Molecular Evidences from the African West Coast (Angola and Equatorial Guinea)

“…DARC-coding gene is polymorphic with multiple alleles as the codominant FY*A and FY*B, which encode for the two antigens – Fya and Fyb. Four genotypes are possible as a result of the combination of the major alleles, Fy(a+b+), Fy(a+b−), Fy(a−b+) and Fy(a−b−) [13], [14], [15]. The first three correspond to a Duffy-positive phenotype, mostly prevalent in Asian and in Caucasian populations and the last one correspond to the Duffy-negative phenotype, mainly prevalent in African people, who are consequently resistant to P. vivax infection.…”

Vivax malaria in Mauritania includes infection of a Duffy-negative individual

“…Some authors [47-50] have attributed the FYX allele to a single polymorphism of the FYB allele (C265T→Arg89Cys) ( FYX1 ), while others have indicated two (C265T and G298A→Ala100Thr) ( FYX2 ) [51-53] or even three polymorphisms (C265T, G298A and G145T→ Ala49Ser) ( FYX3 ) [54]. The point mutation G298A alone did not cause a decrease of the Fyb expression [47].…”