Clinical application of the polymerase chain reaction in the detection of HLA-B27 alleles.

Most patients with ankylosing spondylitis (AS) express HLA-B27 antigens, which in routine clinical practice are conventionally detected by serological assays. Recent reports have been published demonstrating that HLA-B27 can also be detected by the polymerase chain reaction (PCR), with the purported advantages that the latter is faster, cheaper and more reliable than serological detection. In this study the technical reliability of HLA-B27 detection by PCR was demonstrated by the successful amplification of all the defined types of HLA-B27 alleles, while relevant non-HLA-B27 alleles could not be amplified. We have compared the sensitivity, specificity and practical applicability of HLA-B27 typing by serology versus PCR. HLA-B27 typing of 100 random individuals yielded identical results between serology and PCR, indicating that the sensitivity and specificity of serology and PCR are equal. Therefore, PCR with its practical advantages, may be considered the technique of choice for detecting HLA-B27 antigens.