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McKenzie Oster
“As a Ph.D. student, he’d used HeLa to help develop something called fluorescence in situ hybridization, otherwise known as FISH, a technique for painting chromosomes with multicolored fluorescent dyes that shine bright under ultraviolet light. To the trained eye, FISH can uncover detailed information about a person’s DNA. To the untrained eye, it simply creates a beautiful mosaic of colored chromosomes” (Skloot, pg. 234).
Skloot, R. (2009). The immortal life of Henrietta Lacks. Crown Publishers.
1. Levsky, J. M., Singer, R. H., (2003). Fluorescence in situ hybridization: Past, present and future. Journal of Cell Science, 116, 2833-2838 . doi: 10.1242/jcs.00633
Abstract: Fluorescence in situ hybridization (FISH), the assay of choice for localization of specific nucleic acids sequences in native context, is a 20-year-old technology that has developed continuously. Over its maturation, various methodologies and modifications have been introduced to optimize the detection of DNA and RNA. The pervasiveness of this technique is largely because of its wide variety of applications and the relative ease of implementation and performance of in situ studies. Although the basic principles of FISH have remained unchanged, high-sensitivity detection, simultaneous assay of multiple species, and automated data collection and analysis have advanced the field significantly. The introduction of FISH surpassed previously available technology to become a foremost biological assay. Key methodological advances have allowed facile preparation of low-noise hybridization probes, and technological breakthroughs now permit multi-target visualization and quantitative analysis - both factors that have made FISH accessible to all and applicable to any investigation of nucleic acids. In the

future, this technique is likely to have significant further impact on live-cell imaging and on medical diagnostics.
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This source is highly credible because it is from an international peer-reviewed journal and was written by authors who have a strong background in the topic. The authors attended the
Albert Einstein College of Medicine in the Department of Anatomy and Structural Biology. The subject of the journal and article is about the FISH (fluorescence in situ hybridization) technique, which is highly relevant to anatomy and structural biology. Although the article was published in
2003 it provides accurate information about the history and outline of Fish, making the source very credible even though time has passed.
Fig. 2.
State of the art in FISH. (A) Many transcription sites (10) detected using barcoded probes can determine the gene expression pattern of each cell (Levsky et al., 2002) (B-D). Detection of single mRNA molecules using double or triple colored probes (Femino et al., 1998). (E) Detection of 24 chromosomes using spectral imaging (Macville et al., 1997). http://jcs.biologists.org/content/116/14/2833/F2.expansion.html
2. Moter, A. Gӧbel, U.B., (2000). Fluorescence in situ hybridization (FISH) for direct visualization of microorganisms. Journal of Microbiological Methods, 41 (2), 85-112. doi: 10.1016/S0167-7012(00)00152-4
Abstract: As a technique allowing simultaneous visualization, identification, enumeration and localization of individual microbial cells, fluorescence in situ hybridization (FISH) is useful for many applications in all fields of microbiology. FISH not only allows the detection of culturable

microorganisms, but also of yet-to-be cultured (so-called unculturable) organisms, and can therefore help in understanding complex microbial communities. In this review, methodological
3 aspects, as well as problems and pitfalls of FISH are discussed in an examination of past, present and future applications.
This source is very credible as it is peer reviewed, and the authors are highly qualified on the subject. The authors attended the Institute for Microbiology and Hygiene at the Humboldt
University in Berlin, Germany. The topic of the article revolves around understanding microbial communities using FISH, so the authors’ experience in microbiology adds credibility to the article. This article, and others from the same authors, have been cited many times throughout microbiology articles and the scientific community. The authors are from Germany which adds an international scope to the research and may give a different perspective of the topics discussed.
Fig. 2. Direct, (a) and (b), and indirect, (c)–(e), labeling of probes using digoxygenin (DIG), horseradish peroxidase
(HRP) or Tyramide Signal Amplification (TSA). http://www.sciencedirect.com/science/article/pii/S0167701200
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3. Lizard, G., Chignol, M. C., Chardonnet, Y., Souchier, C., Bordes, M., Schmitt, D., Revillard,
J. P. (1993). Detection of human papillomavirus DNA in CaSki and HeLa cells by fluorescent in situ hybridization: Analysis by flow cytometry and confocal laser scanning microscopy. Journal of Immunological Methods, 157 (1-2), 31-38. doi: 10.1016/0022-
1759(93)90067-H

Abstract: CaSki and HeLa cell lines, isolated from human uterine carcinomas and containing
4 integrated human papillomavirus (HPV) DNA type 16 and 18, respectively were used to evaluate the sensitivity of HPV-DNA detection on suspended cells by fluorescent in situ hybridization using flow cytometry and on corresponding cell deposits using confocal laser scanning microscopy (CLSM). HPV DNAs were detected in cell suspensions with biotinylated DNA probes and revealed with a three-step technique: a rabbit antibiotin antibody, a biotinylated goat anti-rabbit antibody and a streptavidin-fluorescein isothuiocynate complex. By flow cytometry,
HPV DNA was detectable only in CaSki cells which contained about 600 copies of HPV DNA per cell. In HeLa cells, with only 20–50 copies of HPV DNA, flow cytometry could not detect
HPV DNA, whereas CLSM permitted visualization of fluorescent labelling of HPV DNA hybrids. Furthermore, CLSM showed good preservation of cellular morphology and the nucleus was clearly recognizable after fluorescent in situ hybridization and counterstaining with propidium iodide. Moreover, this examination confirmed that the fluorescent foci were specifically confined to the cell nuclei.
The credibility of this article is about in the middle, because although it is peer reviewed and from qualified authors, it has not been cited in any other articles and it is rather outdated being from 1993. The information provided on the studies conducted in it may have been highly credible in 1993; however, new studies may have replaced the results found in the study that is being described. This article can be used to look at the use of fluorescent in situ hybridization in history, but should not be taken as fact for the science of present times.
This research has provided more information on the fluorescent in situ hybridization
(FISH) process and what it is used for in not only medicine but all across biology as well. Each source provided a different look at why FISH is important and how it has helped with new

discoveries. The research gave a huge change in perspective of this process from the book “The
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Immortal Life of Henrietta Lacks” by showing that this technique was not just used to make the parts of a cell more visible and look cool, but to make new discoveries. HeLa cells were not just dyed to give a pretty picture to Deborah, but to help detect human papillomavirus in DNA and other research projects. One question that I never fully answered from the passage from this research is how did Christoph Lengauer use HeLa to develop this technique, and when exactly did that occur. Overall, the research provided new insight on what exactly FISH is, and it has sparked a lot of questions about major contributions to science that it has played a part in, and how the technique was formed.