RESUMEN
<p><b>OBJECTIVE</b>To investigate allelic and haplotypic polymorphisms of human leukocyte antigen(HLA) genes at A, B and DRB1 loci in Yantai and Weihai Han population and analyze the genetic relationship between Yantai, Weihai Han population and other populations.</p><p><b>METHODS</b>A total of 4062 unrelated Han ethnic individual from Yantai and Weihai regions were genotyped by polymerase chain reaction-sequence specific olignucleotide probe(PCR-SSOP) for HLA-A, B and DRB1 loci. Allelic and haplotypic frequencies were estimated by maximum likelihood estimation method using Arlequin 3.5 software. Genetic distances were computed, and phylogenetic tree was constructed using Mega5.0 software.</p><p><b>RESULTS</b>Respectively 18, 33 and 13 alleles were observed at HLA-A, B and DRB1 loci. The most frequent alleles were HLA-A*02(0.2935), HLA-B*15(0.1485) and HLA-DRB1*15(0.1621). And the most common three loci haplotype was A*30-B*13-DRB1*07(0.0649). A*33-B*58, A*66-DRB1*13 and B*08-DRB1*03 showed the strongest linkage disequilibrium. Yantai and Weihai Han population has the shortest genetic distance with Jilin Han population (0.0034).</p><p><b>CONCLUSION</b>The HLA-A, B and DRB1 loci are highly polymorphic in Han population from Yantai and Weihai, and this population has closest relationship with Han population from Jilin province.</p>