The E7-associated cell-surface antigen: a marker for the 11p13 chromosomal deletion associated with aniridia-Wilms tumor.

Unbalanced interstitial deletions of the p13 region of human chromosome 11 have been associated with congenital hypoplasia or aplasia of the iris, mental retardation, ambiguous genitalia, and predisposition to Wilms tumor of the kidney. Utilizing somatic cell hybrids containing either the normal or abnormal chromosome 11 from a child with Wilms tumor and aniridia, we previously mapped the E7 cell-surface antigen to the 11p1300-to-11p15.1 region. To localize even further the site of this antigen on chromosome arm 11p, we have produced somatic cell hybrids from the fibroblasts of a second child with Wilms tumor and aniridia and a different deletion of 11p [46,XY, del (11)(pter----p14.1::p11.2----qter)]. Furthermore, the normal and deleted chromosome 11 could also be distinguished on the basis of a restriction fragment length polymorphism for the beta-globin gene. Hybrid cells containing the deleted chromosome were not killed in the presence of complement and the E7 monoclonal antibody (which recognizes E7 cell surface antigen), while hybrid cells containing the patient's normal chromosome 11 were killed. Thus, expression of the E7-associated cell-surface antigen can be mapped to the 11p13 region, and it appears to be a potential marker of the chromosome abnormality associated with aniridia-Wilms tumor.