The results of the human genome project found that only about 1.5% of the genome is actually involved in coding for protein producing genes. Some of the remainder is certainly involved in the regulating the expression of these genes, however, the majority of the DNA in the genome has no currently understood function. The lack of known function for this DNA has earned it the name 'junk DNA' and within this 'junk DNA' are sequences known as pseudogenes. Pseudogenes are believed to be remnants of genes which lost their function.
The technique used in the current paper makes it possible to discover protein coding genes in 'junk DNA', which was previously impossible. The authors found that some pseudogenes actually produce protein, indicating that they have some function. They also found that many of the proteins encoded by pseudogenes were also expressed in cancer cell lines, raising the possibility that expression of the pseudogene encoded proteins may play a role in disease.
Some information for this blog post was obtained from the Science Daily article: Protein Coding 'Junk Genes' May Be Linked to Cancer