G-banding analysis was performed on a cultured human salivary gland adenocarcinoma. Clonal chromosome abnormalities consisted of a 6q- marker and loss of the Y chromosome. The 6q- marker had resulted from a long arm interstitial deletion, del(6)(q22q24). The present results, together with our previous findings of 6q deletions in other types of salivary gland tumors, indicate that deletions of 6q are characteristic for the karyotypic evolution of all major types of malignant salivary gland tumors. A common pathogenetic mechanism for these tumors might well be loss of a tumor suppressor gene located on 6q.