Does a physician have a moral and legal obligation to warn 3rd parties of hereditary risks?

I stumbled upon this looking for something unrelated, and thought ...this is fascinating.
What do you think?

VM -- A Physician’s Duty to Warn Third Parties of Hereditary Risk, Sep 09 ... Virtual Mentor

My doctor obligated to directly tell my son of a condition he may have inherited from me? No. My doctor tells me of the possibilities, instructs me to tell my family, has me sign a waiver that I understand I should relay this information, and not hold my doctor responsible for what happens down the line.

This is an area in which the laws and precedents that we set today are guaranteed to be insufficient in the future. At this time I do not think that doctors are required morally to do so. In the future that may change, and it depends upon the ease and level of control we gain over genetics plus other factors. Nobody knows the future.

"Let thy Discontents be Secrets" -- Benjamin Franklin

Interestingly, lawsuits are arising and doctors are losing.