S4, E6: Public Genomes: To test or not to test? NOVA scienceNOW revisits the question Neil deGrasse Tyson asked himself last season, as he pondered whether to get a personal genetic profile that would predict his chances of contracting one of several serious diseases. In the interest of science journalism, Neil submitted his spit for analysis. But would you? / Algae Fuel: What if you could generate useable biofuels without the problems associated with corn ethanol or plant-based processes, didn't use arable land or fresh water, didn't rely on foodstuffs, cost very little, and could be "tuned" to produce hydrogen? Well, there is such a thing. It's algae, and it just may be our biofuel future. / Mystery of the Gakkel Ridge: Stretching more than a thousand miles deep beneath the Arctic Ocean, Gakkel Ridge is an eerie undersea landscape of volcanoes, hydrothermal plumes, and exotic creatures. But though Gakkel Ridge may be unique on Earth, it bears an enticing resemblance to Europa, one of Jupiter's many moons. Could exploring Gakkel bring us one step closer to finding out if Europa might host life? / Profile-Yoky Matsuoka: Growing up in Japan, Yoky Matsuoka was on her way to becoming a world-class tennis player, but it was hard to find a regular partner. So Matsuoka designed and hoped to build her own: a robotic player that would never get tired. Injuries crushed her tennis dreams, but not her interest in robotics. Now Matsuoka is a leader in the emerging field of neurobotics - a fusion of neuroscience and robotics.