Function of Repetitive DNA
The function of repetitive DNA was illuminated by several lines of genome research showing showing that repetitive DNA is an evolutionary device to catalyze formation of new genes by suppressing gene conversion. The insertion of repetitive transposable DNA sequence, SINEs and LINEs acts to break up DNA homologies and allow new gene variations to evolve The evidence has been gathered here so that a new generation of genomic scientists may examine it in the fresh light of reason.
Gene conversion links similar DNA sequences together. 
It can operate on genes within a multigene family or it can operate interchromosomally on gene homologues. Similar DNA sequences are the substates for gene conversion. Gene conversion is the cohesive force allowing species to clump together as a Natural Kind. The gene pool of a species consists of DNA sequences in a network linked by gene conversion events. Repetitive sequences play the role of uncoupling this network, thereby allowing new genes to evolve. The shorter Alu or SINE repetitive DNA are specialized for uncoupling intrachromosomal gene conversion while the longer LINE repetitive DNA are specialized for uncoupling interchromosomal gene conversion. Interspersed Repetitive DNA at Wiki
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