Hereditary breast and ovarian cancer (HBOC) syndrome is a relatively new science.  This means the landscape is constantly changing.  Here is a recent list of the 'risky genes' that, if mutated, fall under the HBOC syndrome umbrella.

List of Risky Genes

Hereditary cancer is a relatively new science.  In the not too distant past, genetic services only tested for BRCA genes. Today, many additional HBOC syndrome genes have been discovered and more are expected to be discovered.  Those with a family history of cancer who received a negative result for BRCA gene mutations may want to consider being re-tested with a more comprehensive gene panel.  This also goes for those returning a negative result with today's gene panels who may want to revisit genetic testing in a few years when more genes have been added  .  .

As an an example, the RECQL gene was discovered in 2015, but does not yet appear on the above list:

Scientists identify new gene linked to breast cancer