Estimation of the tMRCA for EV71 genotypes based on the VP1 gene. The mean estimated dates are labeled and are represented by grey squares. The taxa are labeled with their sampling dates. A, genotype A; B, genotype B and C, genotype C. Subgenotypes C4b and C4a are proposed to be genotypes D1a and D1b respectively. Black circles and squares indicate EV71 isolates of subgenotype C4 (proposed genotype D) and those of subgenotype C2 respectively from Hong Kong in the present study.
Yip et al. Virology Journal 2013 10:222 doi:10.1186/1743-422X-10-222