Genetics Careers: the Cytogenetic Technologist

Chromosomes are bodies of tightly bound DNA and proteins that reside inside the cells of organisms. These bodies help keep genetic information safe and compact, making replication easy when it's time for cells to divide. Humans have 23 pairs of chromosomes stored in the nuclei of most cells. Half are inherited from the biological mother, half from the biological father.

Chromosomes are genetic material. As such, they are integral to the growth and function of living things. If something is wrong with a chromosome’s structure, or if there is an extra chromosome, this can result in physical and cognitive impairments. Consider Klinefelter's syndrome: a genetic disorder affecting males, it is characterized by the presence of extra X-chromosomal material.

X and Y Chromosomes

Courtesy: NASA

Cytogenetic technologists' laboratories are often in hospitals. They use magnification, staining and other techniques to view and analyze chromosome structure. An example is karyotyping, making a picture of an organism’s pairs of chromosomes and listing them from largest to smallest. A newer technology called fluorescent in situ hybridization (FISH) can create an accurate karyotype.

FISH involves the use of fluorescent probes—pieces of DNA that bind to corresponding DNA on chromosomes. This works because the chemical bases on one DNA strand complement the bases of the other. Therefore, if a piece of DNA is pulled apart and one strand is discarded, it’s simple to work out its sequence. For example, since adenine (A) always pairs with thymine (T), and cytosine (C) with guanine (G), the sequence AATTCG complements the sequence TTAAGC.

Cytogenetic technologists need a good eye for detail, the ability to work independently, and good communications skills to explain their findings to other professionals. Salary and hours depend on employers' specifications.

Technologists typically possess a bachelor’s and/or graduate degree, though this will depend on where they live and the job description. If you are interested in training as a cytogenetic technologist, why not contact an appropriate laboratory to learn more? Ask appropriate employment questions including requirements, job demand, and pay scale.

• Cytogenetic Technology Career Overview, Mayo Clinic website, accessed: May 31^st 2009
• Cytogenetic Technologist, Health Careers Center website, accessed: May 31^st 2009

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