Junk DNA refers to non-coding region in our DNA. Since it was revealed by the Human Genome Project in 2000 that only 2% of the genes produce protein. 98% of DNA has not related in production of protein. Consequently, people defined this region of DNA called junk DNA. However, it has been controversial that does 98% of non-coding DNA have any functions in our body or just evolutionary random meaningless DNA? Since the ENCODE project in 2003, it has been found that this non-coding DNA is actually transcripted into non-coding RNA and actually plays a role in our body. (ENCODE project 2003 was follow-up study from Human Genome Project to identify all functional element of DNA.)

Recent research study led by Dr. Lovorka Stojic from Cancer Research UK Cambridge Institute has shown that one of example of junk DNA, long non-coding RNA (lncRNA) GNG12-AS1 acts as a switch-off for a tumor suppressor gene called DIRAS3.

When lncRNA GNG12-AS1 is out of control, tumor suppressor gene DIRAS3 is downregulated and consequently cells are replicated abnormally and turn to cancer cells. This study gives evidences that there are correlations between junk DNA and tumor suppressor function.

Dr. Lovorka Stojic indicated that this finding could be important to understand how non-coding RNAs functions (another word, junk DNA) and to make therapeutic target strategies to treat cancer.