The Duffy blood group - Blood Groups and Red Cell Antigens - NCBI Bookshelf
The parasite Plasmodium vivax plays a major role in the overall .. into the interaction between Duffy antigen and Plasmodium vivax Duffy. This has influenced the variation in Duffy blood types seen in populations where the malaria parasite Plasmodium vivax, and RBCs that lack the Duffy Fya and . Rayner J. Getting down to malarial nuts and bolts: the interaction between. Background: The negative homozygous condition for the Duffy blood group (Fy-/ Fy-) confers natural resistance to Plasmodium vivax infection. In this direction.
Additionally they are receptors for the chemokine family involved in the regulation of inflammatory processes.
Duffy blood group system | biology | zolyblog.info
This resistance appears to have significantly influenced the distribution of Duffy system phenotypes in areas where malaria is endemic. The etiologic agent, Plasmodium sp. Malaria is caused by infestation of different species of protozoa of the genus Plasmodium: Mortality was also reduced from 3 deaths per 10, cases in to 1. In this same period, there was a considerable change in the transmission dynamics of malaria with concentrations of cases in specific municipalities.
The number of municipalities at high risk, i. Sporadic autochthonic cases occurred in restricted focal areas. Often, infant mortality and morbidity are related to delay in establishing the correct diagnosis because of few clinical features.
This promotes the fertilization process producing zygotes that become invasive and grow and divide thus producing thousands of invasive sporozoites. These migrate through the body and invade the salivary glands of female mosquitoes. Females, when they feed again, inoculate sporozoites in the blood of man, which rapidly migrate into hepatocytes and transform into trophozoites in the liver where they mature and divide to form thousands of merozoites.
The state of the Duffy gene was determined in all individuals, but the Duffy phenotype was not analyzed.
Duffy antigen system
Starting with peripheral white blood cells or epithelial cells from oral mucosa, DNA was obtained through "Salting out" or use of phenol-chloroform. The identification of the different alleles of the Duffy gene was done based on the methodology published by Tournamille et al. Briefly, specific primers were applied to amplify a fragment of 1.
The product of this first reaction was used as template for: The products of the second amplification were subjected to an analysis of the restriction fragments RFLP in the English acronym: The size of the fragments were assessed using the Quantity One software program Bio-Rad as follows: Positive and negative controls were samples of typing now standardized in the laboratory of the Group Health and Community.
Qualitative and quantitative variables were analyzed. Qualitative variables were analyzed by chi square test with the EpiInfo 6. Obtaining genotypic and allelic frequencies and tests of neutrality and genetic structure were done using the "Genepop" program, version 3.
The design of the proposal met with the verbal approval of the local governor of the indigenous community and each individual, or his guardian, who agreed to participate, signed or left their digital fingerprint on the informed consent form. Individuals diagnosed with malaria received, at no cost, the treatment recommended by Colombian standards. This research was considered to be of minimal risk. Results Description of the study population: In total, volunteers were studied.
The ethnic distribution was: Table 1 shows the general characteristics of the population. The probability value p for the relationship of each analyzed variable sex, age, residence area with the ethnicity variable is indicated Frequency of infection by Plasmodium: Among those with an infection, the frequency of each species was: The parasitemia from P. By ethnicity, the average parasitemia from P. Perhaps this finding partly derives from the small size of the groups and notorious variations that are reflected in the high standard deviations Table 2.
No significant relationship was found between the species of Plasmodium and ethnicity. The frequency of the T allele at the locus in Afro-Colombians was 0. The CC and TT genotypes showed frequency of 0. In the locus, the G allele was found less frequently in Afro-Colombians 0. Regarding genotype distribution, the lowest frequency of heterozygote's was found in Afro-Colombians 0.
Table 4 details the genotypic and allelic frequencies in each of the populations studied for the loci evaluated. Meanwhile, in the Amerindian and Mestizo populations there is an excess of heterozygotes at locus In evaluating each locus according to the total population, it was observed that in the locus there is a deficit of heterozygotes while in locus there is an excess of them.
To confirm the above, genetic differences were compared through a tree "Neighbor Joining" NJ and the genetic distance of Cavalli-Sforza. A high degree of genetic differentiation was obtained among the three populations. This means that the gene flow between these two ethnic groups mixed is the smallest in the population structure of La Italia. The shortest distance was found between Amerindians and Mestizos 0. This is contrary to what happened in Amerindians and Mestizos who were predominantly GA genotype.
On the other hand, the Amerindians exhibited a frequency times greater of GG while Mestizos were times more frequently found with AA Fig. The TA haplotype was predominately found in Mestizos. Comparison of the 3 most probable haplotypes ge nerated Harlequin program.
Analysis of association of some variables - On comparing the average number of episodes of malaria in the last year by diplotype and ethnicity, there was no statistically significant difference.
However, on analyzing the number of malaria episodes in the same period according to ethnicity, significant differences were found in Mestizos who had a higher average number of episodes of malaria in the last year vs. Individuals with other diplotypes could be infected by P. The diversity in the population as in the case of age and ethnic composition 25 could influence the presentation of asymptomatic parasitemia.
Duffy Blood Group System and the malaria adaptation process in humans
Nonetheless, at least in the present study, no significant association was found between age and frequency of malarial infection in the differing ethnic groups, so that the relevance of the interaction between age-ethnicity-asymptomatic infections should be more widely explored.
Clinical significance of Duffy antibodies Transfusion reactions Antibodies against the Duffy antigens Fya 8Fyb 9, 10Fy3 1and Fy5 11,12 have all been implicated as the cause of a transfusion reaction.
- Duffy blood group system
- Duffy blood group and malaria.
Anti-Fya is more commonly found in patients who are of African descent in whom the Duffy null phenotype is more common and have sickle cell anemia and therefore may require multiple blood transfusions. Hemolytic disease of the newborn Maternal-fetal incompatibilities within the Duffy blood group system is an uncommon cause of HDN. The disease tends to be mild in nature. The Duffy antigens known to have caused maternal immunization and subsequent hemolytic disease are FyaFyb 17and Fy3 1.
It consists of two exons that span over 1, bp of genomic DNA.
The two main alleles, FYA and FYB, differ by a single nucleotide at position G and A, respectively and they likewise encode Fya and Fyb antigens that differ by a single amino acid at residue 42 glycine and aspartic acid, respectively. Most commonly, a mutation in the promoter region of the FYB allele abolishes the expression of the Duffy glycoprotein in RBCs, but the protein is still produced in other types of cells. Perhaps because the Duffy antigens are expressed in other tissues, these patients do not generally make anti-Fyb or anti-Fy3 Less commonly, the Fy a-b- phenotype is a result of point mutation that introduces a premature stop codon into the coding sequence.
It is unlikely that the truncated Duffy protein is transported to the cell surface, and it is likely that the Duffy protein would be absent from all tissues in individuals who carry this type of mutation. There may be strong anti-Fy3 in these patients Protein The Duffy glycoprotein is a transmembrane protein that spans the RBC membrane seven times and has an extracellular N-terminal domain and a cytoplasmic C-terminal domain.
It shares structural similarity with G-protein coupled receptors but so far, it has not been shown to be a member of this family. The binding site for chemokines, the binding site for P.