Frequency of the DI*A, DI*B and Band 3 Memphis polymorphism among distinct groups in Brazil
Alessandra Kaliniczenko1, Juliana Oliveira Martins1, Bruno Ribeiro Cruz1
1Universidade Federal de São Paulo, Escola Paulista de Medicina, SP, Brazil.
Insights
The DI*B allele is more common in blood donors, while the DI*A/DI*A genotype is rare across all groups. Band 3 Memphis mutation was also more frequent in blood donors, highlighting population-specific genetic variations.
Area of Science:
- Genetics
- Immunology
- Anthropology
Background:
- Band 3 protein, encoded by the SLC4A1 gene, is crucial for red blood cell function and carries Diego blood group antigens (Di a and Di b ).
- Band 3 Memphis is a variant of Band 3, with variant II specifically associated with the Di a antigen.
Purpose of the Study:
- To determine the frequencies of DI*A and DI*B alleles and Band 3 Memphis polymorphism.
- To compare these frequencies across blood donors, sickle cell disease patients, and Amazonian Indians.
Main Methods:
- Genotyping of DI*A/B, normal Band 3, and Band 3 Memphis was performed using Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP).
- A total of 427 blood samples were analyzed, categorized into blood donors (n=206), sickle cell disease patients (n=90), and Amazonian Indians (n=131).
Main Results:
- The DI*A/DI*A genotype was infrequent (0.5%) in blood donors and absent in other groups.
- DI*A/DI*B allele frequency was highest in Amazonian Indians (33.6%), whereas DI*B/DI*B was most prevalent in blood donors (92.2%).
- The Band 3 Memphis mutation was detected in 4.8% of individuals, with a higher occurrence in the blood donor group.
Conclusions:
- The DI*B allele is more common in blood donors, and the DI*A/DI*A genotype is rare in the studied populations.
- Band 3 Memphis also showed higher frequency in blood donors.
- These findings underscore the necessity of examining diverse populations to understand blood group antigen genetics.
Introduction:
The Band 3 is a red blood cell protein that carries the Dia and Dib antigens from the Diego blood system. The SLC4A1 gene encodes Band 3; Band 3 Memphis is a polymorphism of normal Band 3 and has two variants, but only the variant II carries the Dia antigen.
Objectives:
Describe the frequencies of the DI*A and DI*B alleles and the Band 3 Memphis among blood donors, sickle cell disease (SCD) patients and Amazonian Indians.
Methods:
A total of 427 blood samples were collected and separated into three groups: 206 unrelated blood donors, 90 patients with SCD and 131 Amazonian Indians. We performed DI*A/B, normal Band 3 and Band 3 Memphis genotyping, using the Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP).
Results:
The frequency of the DI*A/DI*A genotype was 0.5% in blood donors and it was not found in other groups. The frequency of the DI*A/DI*B was higher in Amazonian Indians (33.6%) and the frequency of the DI*B/DI*B was highest in blood donors (92.2%). All 105 individuals tested were positive for the presence of normal Band 3 and of these individuals, only 5/105 (4.8%) presented the Band 3 Memphis mutation.
Conclusion:
We observed a higher frequency of the DI*B allele in blood donors and a low frequency of the DI*A/DI*A genotype in all groups studied. The Band 3 Memphis was found in a higher frequency in the blood donor group. Our findings highlight the importance of analyzing different population groups to gain a better understanding of the genetic association of blood group antigens.
Related Concept Videos
01:49Multiple Allele Traits
01:57Gene Families
Occasionally these regions can be adapted to take on new roles within the organism, becoming novel genes...
01:26Polymer Classification: Stereospecificity