Experimental Approaches

Gene expression is determined by genetic regulatory systems in the body which establishes where, when and how much genes are switched on/off. The end result is the characteristic expression of different proteins to different extents in different cell types.

For any particular gene, developmental geneticists are interested in which tissues and at what developmental times the gene is transcribed and how much of the resulting protein is made. For this to be achieved there are a variety of experimental procedures that enable a gene's function to be resolved.  

 Developmental studies and experiments are performed to gain a better understanding of the cellular mechanisms that underlie the developmental processes.

 As mentioned in the previous section, model organisms are used extensively in these experiments. This has helped enormously in speeding up the advances in understanding human processes, such as development, and they have also contributed to our knowledge of diagnosing, preventing, treating and curing human diseases.

Reverse genetics and forward genetics are two main branches of experimental procedures that act to identify and determine the function of genes involved in development. Under these two categories comes a wide variety of differnet methods used, and geneticists will choose which one to use depending on what they are specifically investigating, and its suitabilty towards this. They also have to take into account the model organism they are going to select for the study, and if the experimental procedure is compatible with the system chose.

Reverse Genetics 

This is when the functional study of a gene starts with the gene sequence rather than a mutant phenotype. Reverse genetics manipulates genes to identify their functions. A genes function is altered and the effect on the development or behaviour of the organism is analysed. It can be used to investigate the function of all genes in a gene family. This process begins in a manner where the sequence of the gene is known. 

Forward Genetics

Is when the identification of a gene and its function is done by introducing random mutations into the genome and then looking for interesting phenotypes. When a mutant is found the what the gene encodes and how it functions an be investigated by looking at the phenotype the mutation produces. This process begins in a manner where the function of the gene is unknown.