Genomics, genetics and epigenetics – what is the difference and how are they related to blood cancer research?
Genomics, genetics and epigenetics seem to be buzzwords in the medical research area, especially when it comes to finding new treatments and ways to attack cancer. Researchers talk about mutations, malfunctioning genes, over expressed genes and provide you with a string of letters and numbers that are ‘misbehaving’. So, what does all this mean when it comes to finding a better way to treat cancer?
The World Health Organisation defines genetics simply as ‘the study of heredity’. Genetics is focussed on a single gene or a group of genes and the impact on the body. The impact may be hair colour or it may be an inherited disease. Genomics, however, is the study of all the genes and how they function. So, genetics looks at a single gene while genomics looks at all the genes and how they relate and function together. The study of genomics therefore involves analysing the whole genome to look for variations that may be causing a disease or may be causing resistance to treatments. Genomics is a massive undertaking. Humans have 3 billion units of DNA across 23,000 genes, if unravelled it would be the length of almost 70 trips from the earth to the sun and back. Thanks to advances in technology our researchers are able to search for variations and pinpoint rogue genes faster.
Epigenetics is like the switchboard or hard drive to our genes. It is the study of what turns a gene on or off so that is either expressed or turned off and therefore no longer expressed. Puberty, for example, is epigenetics at play. It is trying to understand what triggers the brain to set off a cascade of different hormones to commence the corresponding changes to the body.
How does all this relate to blood cancers? Understanding the genomics of a patient’s blood cancer can help the treating clinician to assign the correct subtype of blood cancer. It can assist in providing a more accurate prognosis, i.e. is your cancer going to progress quickly or slowly and lastly, it can help inform whether targeted therapy is necessary or not. Researchers have identified some genes that are resistant to chemotherapy treatment. In these cases, it is best to treat the patient immediately with a targeted treatment. The more we uncover and understand the better we are at targeting the cancer cells with therapies that will work.
The Christine and Bruce Wilson Centre for Lymphoma Genomics has tested over 862 patients in the 15 months it has been operating helping blood cancer patients with diagnosis, prognosis and access to targeted treatment specific to their blood cancer. Every blood cancer is unique, just like each snowflake. It makes sense to tailor each treatment specifically to each blood cancer to give the best chance of a cure.