Biotechnology is the use of biological agents for technological advancement. Biotechnology was used for breeding livestock and crops long before the scientific basis of these techniques was understood. Since the discovery of the structure of DNA in 1953, the field of biotechnology has grown rapidly through both academic research and private companies. The primary applications of this technology are in medicine (production of vaccines and antibiotics) and agriculture (genetic modification of crops to increase yields). Biotechnology has many industrial applications, such as fermentation, treatment of oil spills, and production of biofuels.

Genetic engineering is the alteration of an organism’s genotype using recombinant DNA technology to modify an organism’s DNA to achieve desirable traits. The addition of foreign DNA in the form of recombinant DNA vectors is the most common method of genetic engineering. The organism receiving recombinant DNA is a genetically modified organism (GMO). If the foreign DNA comes from a different species, the host organism is transgenic. Scientists have genetically modified bacteria, plants, and animals since the early 1970s. In the US, GMOs such as Roundup-ready soybeans and borer-resistant corn are part of many common processed foods.

Nucleic acids can be isolated for further analysis by breaking cells open. Fragmented or whole chromosomes can be separated on the basis of size by gel electrophoresis. Short stretches of DNA or RNA can be amplified by PCR. Use of short tandem repeats and gel electrophoresis can allow differences between individuals to be detected. Embryonic stem cells give rise to all cell types in the body. Stem cells are important tools for biological research, because of their potential to differentiate into other cell types. The term “cloning” may refer to cloning small DNA fragments (molecular cloning), cloning cell populations (cellular cloning), or cloning entire organisms (reproductive cloning).

This diagram shows the basic method of DNA extraction.

DNA sequencing uses gel electrophoresis and DNA probes for medical testing. Scientists can probe nucleic acid samples, such as fragmented genomic DNA and RNA extracts, for the presence of certain sequences. Scientists design and label short DNA fragments, or probes with radioactive or fluorescent dyes to aid detection. Gel electrophoresis separates the nucleic acid fragments according to their size. Preimplantation genetic diagnosis (PGD) uses DNA probes to reduce the odds of having a child with a genetic disease. Genetic testing is performed to identify disease-causing genes. The goal of gene therapy is to cure inheritable diseases.

The first mammal cloned was a sheep born in 1996. Dolly was a product of somatic cell nuclear transfer. This process involves removing the haploid nucleus of an egg cell and replacing it with the diploid nucleus of a donor cell. Vaccines, antibiotics, and hormones are examples of products obtained by recombinant DNA technology. Transgenic plants are usually created to improve characteristics of crop plants.

Dolly the sheep was the first mammal to be cloned. To create Dolly, they removed the nucleus from a donor egg cell. They then introduced the nucleus from a second sheep into the cell, which divided to the blastocyst stage before they implanted it in a surrogate mother. (credit: modification of work by “Squidonius”/Wikimedia Commons)

Genome mapping is similar to solving a big, complicated puzzle with pieces of information coming from laboratories all over the world. Genetic maps provide an outline for the location of genes within a genome, and they estimate the distance between genes and genetic markers on the basis of recombination frequencies during meiosis. Physical maps provide detailed information about the physical distance between the genes. The most detailed information is available through sequence mapping. Information from all mapping and sequencing sources is combined to study an entire genome.

Whole-genome sequencing is the latest available resource to treat genetic diseases. Some doctors are using whole-genome sequencing to save lives. Genomics has many industrial applications including biofuel development, agriculture, pharmaceuticals, and pollution control. Although human genome sequences provide key insights to medical professionals, researchers use whole-genome sequences of model organisms to better understand the genome of the species. Automation and the decreased cost of whole-genome sequencing has led to precision medicine.

Imagination is the only barrier to the applicability of genomics. Genomics is being used for personalized medicine to predict disease risks at an individual level and to study of drug interactions before clinical trials. Proteomics is the study of the entire set of proteins expressed by a given type of cell under certain environmental conditions. In a multicellular organism, different cell types will have different proteomes, and these will vary with changes in the environment. Unlike a genome, a proteome is dynamic and in constant flux, which makes it both more complicated and more useful than the knowledge of genomes alone. Proteomics has been used to study different types of cancer. Different biomarkers and protein signatures are being used to analyze each type of cancer. The future goal is to have a personalized treatment plan for each individual.