(August 2004) Construction a knockout mouse For decades researchers have tried to create tools that allowed for precise control over a specific gene in order to study its function. In the early 1980’s a breakthrough technology known as transgenics or gene transfer was developed [1]. This new technology involved the process of pronuclear microinjection, a method involving the injection of genetic material into the nuclei of fertilized eggs (Figure 1). Following injection, DNA would incorporate into the genome of the cell. The transformed fertilized eggs were then injected back into pregnant females and brought to term. A major downfall of…

(August, 2003) The first inklings of genetic theory can be traced back to a common human experience: the recognition that a child has features similar to those of its parents. This ancient observation is actually one of the cornerstones of genetics and its subsequent offspring, molecular biology. For centuries there was little evidence beyond the anecdotal that transmitted inheritance was a reasonable theory. Though it seemed sensible that a child with the same appearance as its parents likely received these characteristics from them, little evidence supported the notion and instead a good deal of confusion surrounded it. Part of the…

Milestones in DNA research The discovery of DNA structure in 1953 was the starting point of a real scientific and cultural revolution, the ending of which is difficult to predict. The discovery and use of enzymes that copy, cut and join DNA molecules in cells was the next step in this revolutionary course. The development of two major techniques contributed further to this already vertiginous process: the manual DNA sequencing method, which appeared in 1975, and the discovery of the polymerase chain reaction (PCR) in 1985, which allows the million-fold amplification of DNA sequences. A natural consequence of these two…