DR1 and periodontitis: Based on the amplified full-length sequence, primers (DL1 5′-T*G*AGTGAAACCACCGAAGTC-3′, DR1 5′-C*G*TTACTTGTTGTCCACCAG-3′, DL2 5′-ACCACGGATTATTCTGCGGC-3′, and DR2 5′-AAAAGACCATGCTCCCCCTC-3′) were designed to screen the samples from the chronic periodontitis patients and periodontally healthy subjects for the novel TTMV.