Table 1. Composition of Dfam. In addition to the repeat families represented here, Dfam contains 76 non-coding RNA families and 92 satellite families.

	Retrotransposons	DNA transposons	Unknown origin
Human only	428	46	1
Mouse only	544	9	8
All mammals	388	277	62
Zebrafish	1074	766	13
Fly	165	27	10
Nematode	57	98	8