Dumbledore blinked several times, looking faintly disconcerted. Severus carefully controlled his amusement. The Headmaster, he found, occasionally forgot that his potions master was half-blood, had been raised in a Muggle town by a Muggle father, and had spent a rather large portion of his childhood learning Muggle science in an effort to impress Lily Evans (not that it had worked). Dumbledore himself did not do nonmagical research of any kind, and judging from his reaction, was not at all familiar with genetics. Evidently, however, he didn't want to get distracted, and so he took the pause that Severus had learned to identify as "making a mental note', and changed the subject back. "We'll look into it. As I was saying, I do not think the odds of a Potter heir appearing in some other wizarding family are very high. A Squib descendant is more likely, but still not likely."