Cytogenetic studies of cell lines derived from Marek's disease virus-induced local lesions.

Cytogenetic analysis of cell lines derived from Marek's disease virus (MDV) induced local lesions was performed to detect the presence of a chromosomal alteration found previously in cell lines derived from MDV-induced visceral tumors. This chromosomal alteration involves an amplified region on the short arm of chromosome 1. Trypsin G-binding was performed on 12 local-lesion cell lines having various T-cell receptor phenotypes. Eight of 12 cell lines had a diploid female karyotype, and four lines were diploid males. Ten of the cell lines showed a normal G-banding pattern; two lines, however, had the short arm amplification on chromosome 1 (1p+). Thus, the 1p+ alteration does not appear to be necessary for establishment of cell lines from local lesions. The occurrence of the 1p+ alteration in Marek's disease cell lines suggests a possible role for this alteration in late stages of multi-step viral oncogenesis.