HLA-DP types of homozygous typing cells: DPw3 found in three Dw19 HTC

No association between susceptibility to multiple sclerosis and HLA-DPB1 alleles in the French Canadian population

HLA-DPB1 typing was performed using polymerase chain reaction DNA amplification and sequence-specific oligonucleotide probing (PCR-SSOP) which permitted identification of 17 distinct DPB alleles using 15 oligonucleotide probes. The accuracy of this approach was confirmed in an initial study of 26 human B-lymphoblastoid cell lines which demonstrated close agreement between PCR-SSOP and PLT assigned types. A cohort of 47 adult French Canadians was then studied to provide an estimate of DPB1 allelic frequencies in an ethnically homogeneous population. DPB1*0401 was the most frequent phenotype (61.5%) and only DPB1*0101, 0301 and 0402 were also present at frequencies greater than 10%. HLA-DPw4 has been reported to be associated with multiple sclerosis (MS) but our PCR-SSOP analysis of 52 French Canadian MS patients showed no association with either the DPB1*0401 or DPB1*0402 splits of DPw4 or with any other DPB1 allele.