Killer Cell Immunoglobulin-Like Receptors in SFS – Marrow Donor Registry (MK-SFSMDR): Feasibility in Identifying Better Donors

BACKGROUND: Different Killer Immunoglobulin-Like Receptor (KIR) genes are relevant for each donor-recipient pair based on the degree of human leukocyte antigen matching and the specific leukemia subtype. The inhibitory or non-inhibitory effects of haplotype B among unrelated or sibling transplants are a perfect example for inconsistent results. Donors possessing KIR B haplotype show a correlation with decreased relapse risks and enhanced disease-free survival following unrelated donor transplants for acute myeloid leukemia. AIM: The aim of this study was to investigate the KIR gene polymorphism in Scientific Foundation SPIROSKI-Marrow Donor Registry (MK-SFSMDR). MATERIALS AND METHODS: The study sample consisted of 516 healthy unrelated individuals, aged 18–55 years. All individuals were registered donors of the MK-SFSMDR, having signed a Marrow Donor Registration form and provided buccal swabs for analysis. KIR gene content typing was performed by HistoGenetics Lab (Ossining, NY 10562, USA) on Illumina platform. Data analysis was performed using the population genetics analysis package Arlequin. RESULTS: We found that all 16 KIR genes were observed in the MK-SFSMDR donors and framework genes KIR3DP1, KIR2DL4, KIR3DL2, and KIR3DL3 were present in all individuals. The observed frequencies of other KIR genes were as follows: KIR2DP1 (0.971), KIR2DL1 (0.971), KIR2DL2 (0.562), KIR2DL3 (0.882), KIR2DL5 (0.523), KIR3DL1 (0.942), KIR2DS1 (0.0401), KIR2DS2 (0.564), KIR2DS3 (0.312), KIR2DS4 (0.942), KIR2DS5 (0.308), and KIR3DS1 (0.374). We defined 35 genotypes from which one was AA group (genotype ID 1 = 27.13%) and the rest were Bx groups (34 genotypes = 72.87%). CONCLUSIONS: We found that all 16 KIR genes were observed in the MK-SFSMDR donors (n = 516) and framework genes KIR3DP1, KIR2DL4, KIR3DL2, and KIR3DL3 were present in all individuals. The observed and estimated frequencies of other KIR genes were presented. We defined 35 genotypes from which one was AA group (genotype ID 1 = 27.13%) and the rest were Bx groups (34 genotypes = 72.87%). Inclusion of KIR genotypes in molecular screening of bone marrow donors may increase efficacy for stem cell transplantation.