Figure 1.

A) Histologic features of renal tumor - typical appearances of clear cell renal cell carcinoma, characterized by nests of epithelial cells with clear cytoplasm separated by a delicate vascular network (hematoxylin and eosin, ×100). Inset - immunohistochemistry for BRCA1 shows nuclear staining in tumor cells(×100).B) 1- Results of Sanger sequencing of the kidney cancer tissue from BRCA1 mutation carrier - electropherogram shows persistence of frameshif indicating no loss of the wild type allele. 2- Results of Sanger sequencing of germline DNA from the same BRCA1 mutation carrier - electropherogram confirming the presence of BRAC1c.68- 69delAG