Date of Award

Fall 2013

Project Type


Program or Major


Degree Name

Master of Science

First Advisor

John Collins


Introns, segments of genes that get spliced from the transcript before translation, are prevalent parts of many genomes and yet remain largely mysterious. Although their presence in the genome has been known for over thirty years, we still cannot answer the most fundamental questions about introns, such as where did they originate and, how are they gained and lost? In our most stringent dataset, we compared 137,453 intron positions in 6,257 pan-orthologs among four species of Caenorhabditis using a bioinformatics approach. While 82% of intron positions were conserved, we found a remarkable amount of intron variation. We also found evidence suggestion a role of both transcription-mediated processes as well as transposon activity in the gain of novel introns. These results suggest a more dynamic picture of intron gain and loss than previously thought and identify some mechanisms that may be responsible for intron gain.