The gene cluster suppresses germline transposition.

Transposable elements (TEs) are mobile sequences that engender widespread mutations and thus are a major hazard that must be silenced. The most abundant active class of TEs in mammalian genomes is long interspersed element class 1 (). Here, we report that transposition is suppressed in the male germline by transcription factors encoded by a rapidly evolving X-linked homeobox gene cluster.