Background: Human papillomavirus (HPV) is the etiological agent of cervical cancer. HPV genotyping is important to determine the presence of high-risk types. Recently, a new HPV genotyping method, the Roche Linear array genotyping test, was introduced and is compared here with a sequencing-based HPV genotyping system.
Materials and methods: A series of 102 women (age range 30-55 years) shown to be HPV DNA-positive by PCR were typed by sequencing and the Linear array genotyping assay.
Results: The sequence analysis revealed the presence of 80 single high-risk types and 22 single low-risk types. With the Linear array, single infections were found in 46 cases, double infections in 37 cases, triple infections in 12 cases, and more than three in 6 cases. One case positive by sequencing gave a negative result by Linear array. Altogether, a concordant single genotype was found in 93 (91.2%) out of the 102 cases and the single-type concordance between the two assays was significant (Spearman rho = 0.849, p = 0.0001; intraclass correlation coefficient (ICC) (ICC = 0.924, 95% CI 0.888-0.949) (p = 0.0001). The majority of the disparate results were due to the detection of multiple types by the Linear array.
Conclusion: The Roche Linear array is a highly accurate assay for HPV genotyping. This is particularly true in the presence of multiple infections which DNA sequencing is unable to resolve.