Not a gene per se, though it's no surprise a popular science outlet screws this up; given a working clock, they typically do only slightly better than chance at identifying the time of day.

From the cited paper [1], what actually makes the difference is having your two copies of a specific gene (one from each parent) differ from one another in a few specific, relatively common ways.

[1] https://www.gs.washington.edu/news/article.pdf