Germ line BRCA1 and/or BRCA2 mutations were screened in 50 Turkish breast a
nd/or ovarian cancer patients composed of hereditary. familial, early onset
and male cancer groups. Genomic DNA samples were tested by heteroduplex an
alysis and DNA sequencing. Two truncating BRCA2 mutations, one novel (6880
insG) and one previously reported (3034 delAAAC), were found in two out Of
six (33%)) hereditary breast and or ovarian cancer patients. A novel trunca
ting (1200 insA) and a missense (2080A-->G) BRCA1 mutation was found in two
of 27 (7%) individuals in the early onset group. A total of four (8%) dise
ase-causing mutations in 50 breast cancer patients were identified in BRCA1
and BRCA2 genes. In addition, five BRCA1 sequence variants have been ident
ified in 23 patients. These results indicate that BRCA1 and BRCA2 genes are
involved in some, but not all, forms of hereditary predisposition to breas
t cancer in the Turkish population. (C) 2000 Published by Elsevier Science
Ltd.