DNA transcription is the copying of DNA into RNA by RNA polymerase. RNA polymerase is principally responsible for the transcription of a gene and can effectively be regulated by specificity factors, repressors, general transcription factors, activators, and enhancers. Transcription factors are proteins that bind to certain DNA sequences called promotor regions of the DNA and are involved in the process of transcription. These promoter regions do not contain the actual DNA or genetic material for transcription but are rather adjacent to the gene. The transcription factors will regulate what proteins within a cell are being manufactured. More specifically, they influence RNA polymerase to transcribe messenger RNA from certain genes. DNA transcription can be regulated at many different points in the transcription process. The regulation controls when the transcription can begin and essentially how much of the RNA will be manufactured. A regulatory protein is involved in the transcriptional regulation and the transcriptional regulator antibodies can bind to these proteins and affect their mechanism of action.

MeCP2 is a protein that binds to DNA and mediates the repression of transcription through involvement with histone deacetylase. Anti- MeCP2 antibody shows affinity to bind to MeCP2 protein. Defects in this protein are the cause of both Rett syndrome and Angelman syndrome (AS). Rett syndrome is a neurologic disorder which causes mental retardation, loss of speech, and seizures. AS is known as happy puppet syndrome and is similar to Rett syndrome. Autism X- linked type 3 is also thought to be caused by defects in MeCP2. The increased dosage of MeCP2 due to multiple copies of the gene (gene duplication) is thought to be the culprit in causing the mental retardation phenotypes. Anti- FOXP3 antibody detects a section of human FOXP3 protein. The FOXP3 protein is a transcription factor that controls certain immune responses and is thought to play a role in diabetes, infections (autoimmune and immunodeficiency), and anemia.