I couldn't help but be amused by the headline in today's Boston Glob: "Breast cancer genes can come from father". Wow! That pesky Austrian monk was on to something with his crazy ideas! The paper upgraded itself back to the Globe with a decently written story describing a new JAMA article which looked for BRCA mutations in patients with very few female relatives. In a nutshell, the BRCA- phenotype (early predisposition to breast cancer) was hidden in these families due to family structure.
The consequences of this are certainly something to take very seriously: some doctors are not thinking carefully about the paternal side of a woman's family tree when scoping out a rationale for BRCA testing, and insurance companies apparently have been over-emphasizing the maternal side of the tree as well, and in some cases a woman may simply have no (or no known) close female relatives. Clearly the medical world has a Sherpa shortage.
Within a decade or so complete genome sequencing or comprehensive mutational scans will be pretty routine. That won't discount the need for taking a good family history, especially since our ability to interpret those scans may lag the technology for obtaining them