3'-Cluster

A 3'-Cluster is a negative DNA sequence discovered by Singh and coworkers, using a technique known as in vivo selection of an entire exon.

The presence of 3'-Clusters prohibit the SMN2 gene from producing its normal proteins which can lead to Spinal muscular atrophy. 3'-Clusters in association with Exinct have been observed to cause aberrant splicing of exon 7, leading to the production of a short SMN transcript that makes a truncated non-functional SMN protein. Another regulatory element ISS-N1 has been also found to affect the aberrant splicing of exon 7. .