Gene expression is a process where a gene is used to synthesize a product. Most of the time the end product is a protein, but sometimes you can end with non-protein coding genes like ribosomal RNA.
Hereditary information must be passed from the parent cell to the daughter cell.
The Central Dogma states that the information is expressed from the replication of DNA to the transcription of RNA, finalizing with the production of proteins by translation. In each step of the process, control pathways are added which will end in the regulation of gene expression, control of traits, and control of cell function.
We can use specific portions of the code that are unique to a condition or disease by molecular testing. For example, direct nucleic acid testing will detect DNA or RNA that is currently contained in the sample, therefore targeting a specific sequence with complementary probes for the detection or amplification of the target sequence.