PMID- 29124304 OWN - NLM STAT- MEDLINE DCOM- 20190104 LR - 20190104 IS - 1432-1211 (Electronic) IS - 0093-7711 (Linking) VI - 70 IP - 5 DP - 2018 May TI - Modeling coverage gaps in haplotype frequencies via Bayesian inference to improve stem cell donor selection. PG - 279-292 LID - 10.1007/s00251-017-1040-4 [doi] AB - Regardless of sampling depth, accurate genotype imputation is limited in regions of high polymorphism which often have a heavy-tailed haplotype frequency distribution. Many rare haplotypes are thus unobserved. Statistical methods to improve imputation by extending reference haplotype distributions using linkage disequilibrium patterns that relate allele and haplotype frequencies have not yet been explored. In the field of unrelated stem cell transplantation, imputation of highly polymorphic human leukocyte antigen (HLA) genes has an important application in identifying the best-matched stem cell donor when searching large registries totaling over 28,000,000 donors worldwide. Despite these large registry sizes, a significant proportion of searched patients present novel HLA haplotypes. Supporting this observation, HLA population genetic models have indicated that many extant HLA haplotypes remain unobserved. The absent haplotypes are a significant cause of error in haplotype matching. We have applied a Bayesian inference methodology for extending haplotype frequency distributions, using a model where new haplotypes are created by recombination of observed alleles. Applications of this joint probability model offer significant improvement in frequency distribution estimates over the best existing alternative methods, as we illustrate using five-locus HLA frequency data from the National Marrow Donor Program registry. Transplant matching algorithms and disease association studies involving phasing and imputation of rare variants may benefit from this statistical inference framework. FAU - Louzoun, Yoram AU - Louzoun Y AUID- ORCID: 0000-0003-1714-6148 AD - Department of Mathematics, Bar-Ilan University, Ramat Gan, Israel. louzouy@math.biu.ac.il. FAU - Alter, Idan AU - Alter I AD - Department of Mathematics, Bar-Ilan University, Ramat Gan, Israel. FAU - Gragert, Loren AU - Gragert L AD - Bioinformatics Research, National Marrow Donor Program, Minneapolis, MN, USA. AD - Department of Pathology and Laboratory Medicine, Tulane University School of Medicine, Tulane Cancer Center, New Orleans, LA, USA. FAU - Albrecht, Mark AU - Albrecht M AD - Bioinformatics Research, National Marrow Donor Program, Minneapolis, MN, USA. FAU - Maiers, Martin AU - Maiers M AD - Bioinformatics Research, National Marrow Donor Program, Minneapolis, MN, USA. LA - eng PT - Journal Article DEP - 20171109 PL - United States TA - Immunogenetics JT - Immunogenetics JID - 0420404 RN - 0 (HLA Antigens) SB - IM MH - *Algorithms MH - *Bayes Theorem MH - *Donor Selection MH - Genotype MH - HLA Antigens/*genetics MH - *Haplotypes MH - Histocompatibility Testing MH - Humans MH - *Models, Statistical MH - Polymorphism, Genetic MH - Registries MH - Stem Cells/*cytology MH - Tissue Donors OTO - NOTNLM OT - Bayesian inference OT - DNA typing OT - HLA OT - Imputation OT - Rare variants EDAT- 2017/11/11 06:00 MHDA- 2019/01/05 06:00 CRDT- 2017/11/11 06:00 PHST- 2017/08/11 00:00 [received] PHST- 2017/10/23 00:00 [accepted] PHST- 2017/11/11 06:00 [pubmed] PHST- 2019/01/05 06:00 [medline] PHST- 2017/11/11 06:00 [entrez] AID - 10.1007/s00251-017-1040-4 [pii] AID - 10.1007/s00251-017-1040-4 [doi] PST - ppublish SO - Immunogenetics. 2018 May;70(5):279-292. doi: 10.1007/s00251-017-1040-4. Epub 2017 Nov 9.