ABSTRACT
For this study we consulted the Bone Marrow Donors' Registry of Lombardy (Italy) and analyzed 43937 HLA-A,B phenotypes and 13922 HLA-A,B,DR phenotypes. We estimated the HLA-A,B and HLA-A,B,DR haplotype frequencies via the maximum-likelihood method. We analyzed the genetic structure of the 11 provinces of Lombardy by means of Principal Component Analysis and Correspondence Analysis, and estimated the variety of the different haplotypes at provincial level and the percentage of unique phenotypes at village level. We found 11189 different HLA-A,B phenotypes, 661 different HLA-A,B haplotypes and more than 4000 different HLA-A,B,DR haplotypes. We identified 20 villages, in Western Lombardy, very rich in unique/rare phenotypes. Here we report a formula which allows the identification of a putative donor matched for two haplotypes with a recipient. This result may be of great importance for the genetic study of the population of Lombardy and, even more, for bone marrow transplantation programs.
Subject(s)
Bone Marrow Transplantation , Bone Marrow/immunology , HLA Antigens/genetics , HLA-DR Antigens/genetics , Haplotypes , Histocompatibility Testing/methods , Tissue Donors , Alleles , Gene Frequency , HLA Antigens/immunology , HLA-A Antigens/genetics , HLA-A Antigens/immunology , HLA-B Antigens/genetics , HLA-B Antigens/immunology , HLA-DR Antigens/immunology , Humans , Immunogenetics , Italy , Phenotype , Polymorphism, Genetic , Registries , Rural PopulationSubject(s)
HLA-A Antigens/analysis , HLA-B Antigens/analysis , Histocompatibility Testing/methods , Leukocytes/immunology , Polymerase Chain Reaction , Serology , Tissue Donors , Tissue and Organ Procurement/methods , Cadaver , DNA/genetics , False Positive Reactions , Genes, MHC Class I , HLA-A Antigens/genetics , HLA-B Antigens/genetics , Humans , Sensitivity and SpecificityABSTRACT
HLA class I typing by standard microcytotoxicity testing has been unsatisfactory for 14.5% of 1644 cord blood samples. In this study, we evaluated the capacity of PCR-SSP in solving problems in HLA-A,B typing with serological methods. With this aim we have compared serology with PCR-SSP in 100 cord blood samples with doubtful or unreliable HLA-A,B typing. PCR-SSP was successful in amplifying HLA-A,B alleles in all 100 cord blood samples. Forty-six typings gave discrepant results with the 2 methods (serology and PCR-SSP). Typings were considered discrepant also in the case of inability to define a split. For 19 specimens, no serological conclusion was drawn due to high mortality of the cell suspension, while PCR-SSP allowed the definition of a clear typing. In 6 cases it was necessary to infer information from serology to define the current typing. Finally, in 3 other cases it was impossible to exclude or attribute the antigen/allele B67 or B4802. PCR-SSP for HLA-A,B can improve the overall reliability of HLA-A,B typing requiring a small amount of blood although, with the set of sequence specific primers adopted, a number of alleles are still poorly defined.
