Personalized medicine relies on molecular information about the patient and his genome for selecting smart approaches particularly suitable for the individual or group of individuals. This kind of information is largely provided by molecular techniques and analyses that are summarized as omics-technologies. Omics in this respect stands for analysis of a whole data space called an -ome, This would be, for example, the whole genome, or the whole transcriptome etc., whatever can be found collectively in a cell, and organ or the whole organism. Consequently, analysis of any -ome data is called the respective -omics.
I will introduce the different -omics fields first very briefly and then in a bit more detail in separate blog entries. This should facilitate quickly locating special information for reference.
The major -omics categories covers in this blog:
Determination and analysis of the genomic DNA sequence of a cell, a tissue or an individual in order to detect aberrations from the average. Genomics is used to detect known genetic risks for diseases or predispositions for diseases.
Detection of chromatin changes that do not involve any changes in the genomic DNA but affect the chemistry around the DNA and the proteins that DNA is wrapped around (nucelosomes). Epigenomics detects reprogramming of areas that can lead to disease not by mutation but by changed program execution in the cell or body.
DNA (double-stranded,the helix) is transcribed into a copy made of RNA (single stranded), which the detaches from the DNA and can travel through the cell. So-called messenger RNAs (mRNAs) carry the instructions for all proteins a cell produces. The mRNA sequence is read and translating into a protein sequence by special protein factories (ribosomes) assembling amino acids into a protein chain. The nature as well as the relative amount of RNA produced by a cell or tissue is informative for changes in the cell program. Such changes may lead to disease even before the disease becomes clinically apparent. Transcriptomics and Epigenomics are tightly interwoven, both influencing the other.
Fig 13: Relation of the five major -omics fields to events in the cell
Once mRNA have been translated into proteins these proteins travel to the site of action in the cell. Many proteins are also fine-tuned by chemical modifications (e.g. phosphorylation) which adapts them for a particular job, or serves to activate some function of the protein. Proteins are the most frequently used biomarkers for disease-related changes and can be measured readily in body fluids such as blood, saliva, or urine.
All food we eat is broken down in our stomach and gut into small units that the body can absorb. Later on this processed food is used to produce all the metabolites the body needs to generate energy, build body mass or repair damaged parts (e.g. would healing). The whole collection of these metabolites including the handling proteins constitute the metabolome of a cell, a tissue or a body.
I will concentrate on these five categories although several more such as Lipidomics have been created in the meantime. However, the mentioned five have currently the major impact on personalized medicine and its development.
In the next five blog entries I will go into a bit more detail for each of these major -omics applications highlighting the following points:
- What is the major result used in personalized medicine?
- Which body samples are required to carry out the experimental analysis?
- Which basic technologies are behind this -omics?
- What are the most likely next advances and how would they improve application for personalized medicine?
What’s coming up next?
Next week the -omics series will focus on the first part, genomics along the four main questions mentioned above.