A composite transposon is similar in function to simple transposons and insertion sequence (IS) elements in that it has protein coding DNA segments flanked by inverted, repeated sequences that can be recognized by transposase enzymes.
A composite transposon, however, is flanked by two separate IS elements which may or may not be exact replicas.
Composite transposons will also often carry one or more genes conferring antibiotic resistance.
Two SINEs may act in concert to flank and mobilize an intervening single copy DNA sequence.
This was reported for a 710 bp DNA sequence upstream of the bovine beta globin gene.