Ala67Thr mutation in the poliovirus receptor CD155 is a potential risk factor for vaccine and wild‐type paralytic poliomyelitis

Poliovirus infections can be asymptomatic or cause severe paralysis. Why some individuals develop paralytic poliomyelitis is unknown, but a role for host genetic factors has been suggested. To investigate if a polymorphism, Ala67Thr, in the poliovirus receptor, which has been found to facilitate increased resistance against poliovirus‐induced cell lysis and apoptosis, is associated with increased risk of paralytic poliomyelitis, poliovirus receptor genotyping was undertaken among Italian subjects with vaccine‐associated (n = 9), or with wild‐type paralytic poliomyelitis (n = 6), and control subjects (n = 71), using RFLP‐PCR and pyrosequencing. Heterozygous poliovirus receptor Ala67Thr genotype was found in 13.3% of the patients with paresis and in 8.5% of the controls (Odds Ratio = 1.667). The frequency of Ala67Thr among the controls is in agreement with earlier published data. It is concluded that the Ala67Thr mutation in the poliovirus receptor is a possible risk factor for the development of vaccine‐associated or paralytic poliomyelitis associated with wild‐type virus. J. Med. Virol. 81:933–936, 2009. © 2009 Wiley‐Liss, Inc.