Supervisors info:
Μαριάννα Πολίτου, Καθηγήτρια, Ιατρική Σχολή, ΕΚΠΑ
Αργυρή Γιαλεράκη, Αναπληρώτρια Καθηγήτρια, Ιατρική Σχολή, ΕΚΠΑ
Κωνσταντίνος Σταμούλης, Αιματολόγος, Επιστημονικός Διευθυντής, Ε.ΚΕ.Α
Summary:
The Duffy antigen system, after its discovery and description about 70 years ago, is a subject of study and research not only due to its clinical importance but also its role in the characterization of the different populations on our planet and the assessment of their affinity. The Fy(a) and Fy(b) antigens of the Duffy system are coded by the corresponding alleles (FY*A, FY*B) which differ by one base (125G>A) and determine the phenotypes Fy(a+b+), Fy(a+b-), Fy(a-b+). The phenotype Fy(a-b-) is common in Africans and rare in Caucasians. It is the result of the point mutation -67T>C in the GATA box of the FY gene which inhibits the expression of the gene. In addition, variations of the FY*B gene, the most important of them being the 265C>T mutation, modify the expression of the antigen Fy(b), resulting in weak or ambiguous serological results.
GOAL: The study of the Greek population regarding the Duffy system and the register of the frequency of the alleles as they result from the molecular analysis of the genotype, with emphasis on the detection of the Fy(〖b+〗^weak) phenotype.
MATERIAL – METHOD: 1043 samples from several regions of Greece were examined, which were sent to the Immunohematology laboratory of the National Blood Donation Center for further investigation of their red blood cell phenotype with a molecular method. DNA was extracted from peripheral blood and 11 antigenic systems, among which the Duffy system, were standardized with the molecular method Human Erythrocyte Antigen BeadChip. For the standardization of the Duffy system the method detects the three polymorphisms: 125G>A(Fya/Fyb), -67T>C(GATA,silencingFY), 265C>T(FYx)[Fy(b+weak)]
RESULTS: From the processing of the results occurred the frequencies of Duffy phenotypes as follows: Fy(a+b+):44%, Fy(a+b-):19.08%, Fy(a-b+):33.93%, Fy(a-b-):0.29%, (Fyb+weak):2.68% as well as the percentages of the Duffy alleles FY*A: 0.420, FY*B: 0,580 and FY*02W.01:0,028 in the Greek population, which are consistent with the results of the 1000 Genome Project (Blood Trans Data 2018).
CONCLUSION: The frequencies of the alleles that were registered for the Greek population are consistent with their frequencies in Caucasians as registered in other studies and in the 1000 Genome Project. Furthermore, it appears that the molecular standardization is essential in cases of deviations, such as the case where a weak expression of the Fyb can be characterized as negative phenotype.
Keywords:
Duffy, Antigens, Alleles, Frequency, Greece