APC and neoplasm: Capillary sequencing of genomic DNA from the D61540 tumor, its xenografts, and from the normal adjacent colon tissue from this patient confirmed the heterozygous variant at position 861 in the parental tumor and xenografts, but revealed only the wild type APC sequence in the normal adjacent colon, suggesting that the variant seen in the tumor and xenografts was indeed a tumor-specific mutation.