Introduction:
Transgenesis is the process by which new characteristic(s) can be introduced into an organism that it did not have previously. Exogenous gene(S)– called transgene- are introduced into an animal through the use of recombinant DNA technology. The extra genes or gene may come from same species or from a completely different species. Transgenesis has many beneficial applications for human application such as producing milk with human proteins, which help with treatment of emphysema, disease models, create high value products to be used on human therapy.
Transgenic cows & modified milk
Cow’s milk is made up of water, sugar, fat, proteins, vitamins and minerals. Casein is a key protein making for 80% of the total protein found in milk. The protein casein holds nutritional value and processing properties, thus making it the most valuable component in milk. Milk from casein transgenic cows produce double the casein than from traditional cows. These cows have both animal and human benefits such as:
* Improving the health growth and survival of calves * Prevent animal diseases such as mastitis * Milk for humans is healthier * Assist the processing of milk into dairy products, such as cheese.
Making a transgenic cow: over all process
The first step used in making a transgenic cow is to design the gene construct. This will contain all the information needed for transfection as well as the desired gene expression. The gene construct will only be active in the mammary glad and will only be expressed at late pregnancy and du ring lactation. The gene construct, a unit of DNA, contains an antibiotic resistance gene. This is due to the treatment of cells after the gene transfer with an antibiotic. This allows for those cells that successful express the ABR gene to be only ones to survive. The gene construct will also include a tissue specific promoter sequence. This ‘promoter’ signals the start the expression of the