High-resolution HLA-A, HLA-B, and HLA-DRB1 haplotype frequencies from the French Bone Marrow Donor Registry.

We have estimated human leukocyte antigen (HLA) haplotype frequencies using the maximum likelihood mode, which accommodates typing ambiguities. The results of the frequency distribution of the 7015 haplotypes obtained are presented here. These include a total of 114 HLA-A, 185 HLA-B, and 76 HLA-DRB1 unique alleles at each locus.

HLA phenotypes of candidates for HSCT: comparing transplanted versus non-transplanted candidates, resulting in the predictive estimation of the probability to find a 10/10 HLA matched donor.

In order to study the impact of human leucocyte antigen (HLA) polymorphism distribution in identifying a matched haematopoietic stem cells unrelated donor (UD), we performed a multi-centric retrospective analysis with the aim of comparing the HLA-A, HLA-B, HLA-C, HLA-DRB1 and HLA-DQB1 phenotypes of 2126 patients (772 patients for whom a donor search failed to identify a matched UD, and 1354 patients who received a 10/10 allele level matched UD). Our results showed that rare HLA-C is often responsible for difficulty in identifying a donor. This locus may add a degree of complexity to a supposed 'frequent' HLA-A HLA-B and HLA-DRB1 phenotype, turning this phenotype into a less frequent one.

Comparative validation of computer programs for haplotype frequency estimation from donor registry data.

Estimation of human leukocyte antigen (HLA) haplotype frequencies from unrelated stem cell donor registries presents a challenge because of large sample sizes and heterogeneity of HLA typing data. For the 14th International HLA and Immunogenetics Workshop, five bioinformatics groups initiated the 'Registry Diversity Component' aiming to cross-validate and improve current haplotype estimation tools. Five datasets were derived from different donor registries and then used as input for five different computer programs for haplotype frequency estimation.

Double umbilical cord blood transplantation for hematological malignancies: a long-term analysis from the SFGM-TC registry.

Allogeneic hematopoietic stem cell (HSC) transplantation is a curative treatment for many hematologic malignancies for which umbilical cord blood (UCB) represents an alternative source of HSCs. To overcome the low cellularity of one UCB unit, double UCB transplantation (dUCBT) has been developed in adults. We have analyzed the outcome of 136 patients who underwent dUCBT reported to the SFGM-TC registry between 2005 and 2007.

Does high-resolution donor typing of HLA-C or other loci upon registration confer advantages to patients?

Our study compared all requests for confirmatory typing (CT requests) received in our center between May 2007 and December 2009 (n = 134) for donors issued from 3 groups defined by different human leukocyte antigen (HLA) loci typed at different levels of resolution. We observed a significant advantage for volunteers when HLA-C 2-digit typing was available or with HLA-A, -B, -C, -DRB1 4-digit typing compared with generic HLA-A, -B, -DRB1, -DQB1 DNA typing: increased percentage of CT requests (p < 0.001), increased rate of donor selection for donation (p < 0.