Types

• The first and most common type of gene transfer is called vertical gene transfer. This is the process of transferring DNA and RNA to organisms of the same species. When two organisms mate, their genes are vertically transferred to their spawn, which will have the same general makeup as the parents. Horizontal gene transfer, however, is the process by which genetic material is passed between two different organisms. One example of this is when a bacteria of one type transfers genes that protect it from an antibiotic to another bacteria of a completely different type.
  
  

History

• Vertical gene transfer has been studied for some time now and linked into the evolutionary theories of Darwin and his successors. While the exact term may not always be used, it is even taught to some degree in public schools to kids. Horizontal gene transfer, however, first really started to be researched in the 1950's. Japanese scientists found that different types of bacteria could transfer genetic material to other types, which explained why different bacteria were all becoming resistant to some antibiotics. It wasn't until 1984 that western scientist Michael Syvanen published a paper detailing the existence and importance of horizontal gene transfer. In 2007, it was noted that this type of gene transfer is important among single celled organisms and those with no cell walls (prokaryotes). It also made genetic engineers worry that certain DNA may taint research in the future because of gene transfer.
  
  

Function

• Both types of gene transfers function in different ways. In vertical gene transfer it's a mix of two parents' genetic material that gets passed on to offspring. In single-celled organisms the genes are split and two separate cells will form, both sharing the same genetic code. Horizontal gene transfer works in a few different ways and occurs on the cellular level. In bacteria it is possible for cells to be altered when foreign genetic materials are introduced. This could happen normally when more than one type of bacteria live near each other, or foreign DNA can be introduced in a lab. Bacteriophage are also known to take genetic material from other bacteria and insert it in their own, which is a process called transduction.
  
  

Benefits

• There are some scientific benefits that can be derived specifically from horizontal gene transfer. It is still in its infancy as far as study and experimentation is concerned, but it is already being used in genetic engineering practices. Horizontal gene transfer allows scientists to implant foreign genetic information into not only bacterial, but many other prokaryotes. They are even able to do so in some multi-celled plants and organisms. Plants, especially, because their chloroplasts are very similar to older bacteria.
  
  

Significance

• The study of gene transfer is very important to the realms of biology, genetics, and evolution. By understanding how genetic material is passed between living things, we can get a better understanding as to how various species has evolved over time. By inserting genes into cells in a laboratory through replication of natural processes, geneticists can begin to understand the workings of bacteria and other organisms and even make discoveries into protecting humans against bacterial diseases.