A gene product is the biochemical material, either RNA or protein, resulting from expression of a gene. A measurement of the amount of gene product is sometimes used to infer how active a gene is. Abnormal amounts of gene product can be correlated with disease-causing alleles, such as the overactivity of oncogenes which can cause cancer. A gene is defined as "a hereditary unit of DNA that is required to produce a functional product". Regulatory elements include: Promoter region TATA box Polyadenylation sequences Enhancers These elements work in combination with the open reading frame to create a functional product. This product may be transcribed and be functional as RNA or is translated from mRNA to a protein to be functional in the cell. RNA products RNA molecules that do not code for any proteins still maintain a function in the cell. The function of the RNA depends on its classification. These roles include: aiding protein synthesis catalyzing reactions regulating various processes. Protein synthesis is aided by functional RNA molecules such as tRNA, which helps add the correct amino acid to a polypeptide chain during translation, rRNA, a major component of ribosomes (which guide protein synthesis), as well as mRNA which carry the instructions for creating the protein product. One type of functional RNA involved in regulation are microRNA (miRNA), which works by repressing translation. These miRNAs work by binding to a complementary target mRNA sequence to prevent translation from occurring. Short-interfering RNA (siRNA) also work by negative regulation of transcription. These siRNA molecules work in RNA-induced silencing complex (RISC) during RNA interference by binding to a target DNA sequence to prevent transcription of a specific mRNA. Protein products Proteins are the product of a gene that are formed from translation of a mature mRNA molecule. Proteins contain 4 elements in regards to their structure: primary, secondary, tertiary and quaternary. The linear amino acid sequence is also known as the primary structure. Hydrogen bonding between the amino acids of the primary structure results in the formation of alpha helices or beta sheets. These stable foldings are the secondary structure. The particular combination of the primary and secondary structures form the tertiary structure of a polypeptide. The quaternary structure refers to the way multiple chains of polypeptides fold together. Protein functions Proteins have many different functions in a cell and the function may vary based on the polypeptides they interact with and