A group of Irish scientists has discovered that a supposedly 'dead' pseudogene is, in fact, active. The gene, DHFRL1, was long thought to be inactive, however new research, published in the US Proceedings of the National Academy of Sciences, suggests this is not the case.
'Scientists have known about these 'zombie' or pseudogenes for decades but the genes were always considered dead and inactive', said Dr Anne Parle-McDermott, lecturer in genetics at Dublin City University and head of the research group who made the discovery.
Pseudogenes are inactive relatives of known genes, which, through either mutations or dysfunctional RNA, do not produce proteins. However, due to their similarity and shared ancestry with known functional genes they can reveal interesting information about the evolution of the genome.
Dr Parle-McDermott and her team were investigating the DHFR gene, which involved in metabolism. It is also a primary target for leukaemia chemotherapy due to its central role in cell growth. However when its associated pseudogenes were investigated, the team were surprised to find that one, DHFRL1, was active and helped regulate energy within the cell.
'[This] finding has huge implications, given many of the thousands of known pseudogenes may not be zombies at all', Dr Parle-McDermott said. 'It is important for a number of reasons, in the cancer field for one. It represents a new target that people didn't know about until now'.
'A combination drug therapy could target both the primary gene DHFR but also its mutant copy. We think this might be a better treatment for cancer', she continued.
This could also be an important finding for spina bifida risk assessment. DHFR has been shown to regulate folic acid metabolism, a key factor in the protection of spina bifida. Testing for mutations in DHFRL1 could help determine the risk a mother has for having a baby with the condition.