TABLE 4.

Mutations in 4/44 Merlin-UL128L^mut-derived viruses following passage in fibroblasts

Location of mutation (nt)a	ORF(s) affected	Mutation and/or coding effect	Mutant population (% of sequenced population)
29048	UL23–UL24, intergenic	C>T	55
29531–31054	UL23–UL24	1,504-bp deletion	64
BAC-240244	US29–US34A	2,215 nt of the left-hand end of the BAC vector remains; there is a 72-nt duplication of a BAC sequence, then a deletion encompassing the remainder of the BAC cassette, and a deletion of 5,076 nt of the HCMV coding sequence to the right of the BAC	100
18049–18050	UL10	1,338-bp insertion (1,329 bp of E. coli sequence plus 9 bp of duplicated viral sequence)	76
206155–206156	US11	1,190-bp insertion of E. coli IS150, plus a 3-nt duplication of viral sequence	100
206155–206156	US11	1,190-bp insertion of E. coli IS150 (opposite orientation to above)	100

^aRelative to Merlin-BAC (GenBank accession number GU179001.1). nt, nucleotide.