High-resolution HLA allele and haplotype frequencies of the Saudi Arabian population based on 45,457 individuals and corresponding stem cell donor matching probabilities.

We estimated HLA allele and haplotype frequencies of the Saudi Arabian population from a sample of 45,457 registered stem cell donors. The most frequent HLA alleles were A02:01g (18.5%), C06:02g (16.1%), B51:01g (14.1%), DRB107:01g (16.2%), DQB102:01g (30.5%), and DPB104:01g (33.6%). The most frequent 5-locus haplotypes were A02:05g~C06:02gB*50:01gDRB107:01g~DQB102:01g (1.73%), A02:01g~C06:02gB*50:01gDRB107:01g~DQB102:01g (1.66%), and A26:01g~C07:02gB*08:01gDRB103:01g~DQB102:01g (1.38%). Furthermore, we used the calculated haplotype frequencies to estimate stem cell donor matching probabilities for Saudi Arabian donor and patient populations under various matching requirements. These results are relevant for strategic donor registry planning in the Kingdom of Saudi Arabia.