Laboratory Technician

Technicians must possess a variety of skills, depending on the work being done in the laboratory in which they work. For example, a technician in a laboratory that studies human genetic polymorphisms will be skilled in the techniques of DNA isolation and DNA sequencing. DNA may be isolated from cultured human cells, which the technician would grow, or from tissue biopsies or blood samples. The technician must exercise great care to prevent accidental contamination of the samples.

Following (chemical) extraction of DNA from the material, the technician will amplify the region of the gene under investigation in an enzyme-catalyzed DNA sequencing reaction. The reaction products, which are pieces of DNA of various lengths, are loaded by the technician onto a thin gel and separated from one another according to size by applying an electric current to the gel. A computer-controlled laser excites fluorescent dye molecules that the technician has chemically attached to the DNA, and a photodetector records the color. The laboratory technician will operate the DNA sequencing machine, supervise the electronic data collection, and, in general, assure the accuracy of the DNA sequence obtained. Good communication skills are an important part of a technician's qualifications, as is the ability to follow (and give) instructions correctly.

In 2000, at Genetic ID, the nation's largest genetic testing lab in Fairfield, Iowa, a technician uses the triple check method to narrow results.

In a protein structure laboratory, on the other hand, the technician must have expertise in protein purification. Since relatively large amounts of protein may be required for structure determination, the gene encoding the protein may be placed into bacteria using recombinant DNA techniques. The bacteria can then be induced to produce (express) significant quantities of the protein. The technician is in charge of growing the bacteria and seeing whether the protein is properly expressed. Next, the technician breaks open the bacterial cells by mechanical means, and purifies (separates) the protein of interest away from contaminating proteins and nucleic acids using a series of chromatographic techniques. The technician must know how to detect and quantify proteins and enzymes.