High occurrence of BRCA1 intragenic rearrangements in hereditary breast and ovarian cancer syndrome in the Czech Republic

Table 1 Molecular genetic testing in 290 Czech high-risk families

Phenotype of families tested for BRCA1/2 mutations*	Number of families/patients	BRCA1 mutation (%)	BRCA2 mutation (%)	Overall mutation (%)	Phenotype and number of families tested for BRCA1 deletions*	Number of BRCA1 deletions detected
HBOC+HOC	105	51 (48.6%)	9 (8.6%)	60 (57.2%)	HBOC 36	4
					HOC 9	1
					Σ 45	5/45 (11.1%)
					5/56 ~8.93% of *BRCA1* mutations
HBC	185	35 (18.9%)	23 (12.4%)	58 (31.3%)	0 × brca<50 29	-
					1 × brca<50 52	1
					2 × brca<50 28	1
					3 × brca<50 15	-
					4 × brca<50 3	3
					Σ 127	5/127 (3.9%)
					5/40 ~12.5% of *BRCA1* mutations
					Overall 172	10/172 (5.8%)
					10/96 ~10.4% of *BRCA1* mutations
Overall	290	86 (29.7%)	32 (11.0%)	118 (40.7%)		10/290 (3.4%)

*See Materials and methods, Patients and criteria for testing. Only deleterious mutations are considered. HBOC – hereditary breast and ovarian cancer syndrome; HOC – hereditary ovarian cancer syndrome; HBC – hereditary breast cancer syndrome.

ISSN: 1471-2350