  For example, the causal relationship between genes and the particular proteins that result in phenotypes is called the Central Dogma. According to the Central Dogma, information flows from DNA to RNA to protein, and not in the other direction. DNA specifies messenger RNA in a process called transcription. Messenger RNA plays a role in specifying the amino acid sequence of a protein which is the fundamental structure of an organism's phenotype. Feminist and non-feminist philosophers of biology, along with many biologists, have pointed out that this causal chain is extremely complicated and that a particular genotype can result in different phenotypes in different contexts. There are gene regulation mechanisms that turn genes on and off, and control the rate of transcription. There are hereditary mechanisms whereby once a portion of DNA is rendered inactive in a cell it remains inactive in all of that cell's descendents. The cellular environment affects what DNA is transcribed and the fate of particular DNA transcripts. A sequence of DNA does not uniquely specify a particular protein. The machinery of the cell processes the RNA transcript. During this processing different portions of an RNA strand can be spliced out resulting in a different end products, which means that same DNA sequence can result in different proteins and different phenotypic traits. The nature of the relationship between a sequence of DNA and the traits of an organism is complicated. Although genes make a difference in an organism's phenotype, they are not the sole causes determining that phenotype. Simple pictures of genetic determinism are not supported by molecular biology.