In 2002, my dad, Martin Doctoroff, died of ALS. At the time, we thought it was a tragic fluke, as is the case with the vast majority of ALS patients. But when his brother, Mike, was diagnosed in 2008, it was clear the disease wasn’t random. Ever since then, my family has been living with a spectre that was always vaguely present. Now, unfortunately, it appears very likely that I have ALS, too.