Transfection is a process in which molecules such as DNA, RNA, oligonucleotides, and proteins are introduced into the recipient cell, integrating into the chromosomal DNA of the recipient cell. Transfection differs from transduction in a way that DNA transfer can be mediated by non-viral methods in transfection. Examples of non-viral methods are chemical-based transfection (e.g. by precipitating DNA with calcium ions, by highly branched organic compounds such as dendrimers, by cationic liposomes, and cationic polymers such as polyethylenimine), non-chemical methods (e.g. electroporation, cell squeezing, sonoporation, optical transfection, protoplast fusion, hydrodynamic delivery), and particle-based methods (e.g. gene gun, magnetofection, impalecfection, and particle bombardment).
The process is also described as transformation. However, transformation can also refer to the alteration of normal cells to cancer cells (such as caused by tumour viruses).
Transfection is carried out to understand and find a way to treat genetic disorders.
Word origin: Latin trāns (across, on the far side, beyond) + infection