CCR5 Delta 32 Allele Frequency in Argentinean Cord Blood Donors

ROCA VALERIA; FERNANDEZ SOUTO DANIELA; ROSELLO JULIETA; SUAREZ SILVINA; MANGANO ANDREA; GAMBA CECILIA; KUPERMAN SILVINA

San Diego

Congreso; AMERICAN ASSOCIATION OF BLOOD BANKS, ANNUAL MEETING 2017; 2017

AMERICAN ASSOCIATION OF BLOOD BANKS

CCR5 delta 32 allele frequency in Argentinean Cord Blood DonorsThe identification of a 32 base pair deletion in the cc-chemokine receptor 5 gene (CCR5 delta 32 allele) that has direct correlation with resistance to HIV infection has prompted worldwide investigations of the allele frequency in different populations, with special interest in Cord Blood Banks. Since the Argentinean is a mixed population, with South-American as well as European ancestry, we aim to study the CCR5-delta 32 allele frequency in cord blood samples.Methods: We report the frequency of this allele, detected by PCR-RFLP, in 220 cord blood donors enrolled according to standard procedures from the Argentinean population. The ethnic origin was collected by a survey at the time of recruitment, and samples divided in 4 groups A: Latin-American from European ancestry (60% of the samples), B: South-American (25% of the samples), C: Mixed AB (13% of the samples); D: other origin (1% of the samples). In order to further characterized our ethnic populations, we also studied locus HLA-A; -B and -DRB1 (by PCR-SSO) and calculated the allele frequencies in groups A and B.Results: Overall, 6.8% were heterozygous for the mutation, distributed on each group as follows: 9.02% Latin-American from European ancestry, 1.82% South-American, 6.9% Mixed AB population; 0% other origin. There were no homozygous individuals in the samples studied. Regarding HLA frequencies, results are shown in Table 1. Top Antigen frequenciesLatin-American from European AncestrySouth-AmericanA* 020,267A* 020,364A* 030,118A* 030,100A* 010,111A* 240,082A* 240,103A* 010,073B* 350,141B* 350,255B* 440,103B* 440,109B* 070,088B* 070,091B* 080,076B* 510,082DRB1* 110,156DRB1* 040,173DRB1* 040,145DRB1* 080,118DRB1* 070,118DRB1* 140,100DRB1* 150,111DRB1* 130,091Conclusion: The frequency observed for CCR5 delta 32 allele is lower than that reported for European populations but consistent with the lack of presence in South-American originary populations. Also, we found allele frequencies in group A to be more resemblant to Caucasian population and group B to Hispanic population, according to OPTN/UNOS data base (https://www.transplantpro.org/news/kidney/optn-public-comment-proposal-offers-alternate-cpra-calculation-method/) supporting the idea of a mixed population. It is worth noticing that the samples selected belong to 3 different regions through the country, being the most distant collection center 935km from the bank. Further studies will be needed to increase the number of geographical regions as well as ethnic groups from our country.