Table 1.

Hereditary breast-ovarian cancer genes in Russia

Gene	Major mutations	Frequency in healthy subjects	Frequency in “high-risk” (familial and/or bilateral and/or young-onset) breast cancer patients	Frequency in non-selected breast cancer patients	Frequency in ovarian cancer patients	References
BRCA1	5382insC, 4153delA, 185delAG	~ 0.1%	~ 10%	2–4%	> 10%	[18–26]
CHEK2	1100delC, IVS2+1G>A	< 1%	~ 5%	~ 2%	<1%	[26–29]
NBS1	657del5	0.5%	~ 1%	0.7%	<1%	[29, 30]