This web page was produced as an assignment for an undergraduate course at Davidson College.

Print-lessness in Print

http://www.pdb.org/pdb/explore/explore.do?structureId=3UVD
SMARCA4, a related protein of the SWI2/SNF2 family

 

This page will compare a primary research article entitled “A Mutation in a Skin-Specific Isoform of SMARCAD1 Causes Autosomal-Dominant Adermatoglyphia” (Nousbeck et al., 2011) and two popular news article about the same story. One of these articles comes from the BBC news website (BBC, 2011); the other is an article from the New York Times website (Bhanoo, 2011).

Biological Context

Adermatoglyphia is a very rare, autosomal-dominant condition that describes in congenital absence of fingerprints. People afflicted with the disorder have no prints or “epidermal ridges” on their fingers, toes, palms, and soles of their feet from birth. They also have reduced perspiration in these affected regions. These ridges form in unafflicted people around 24 weeks after fertilization. To date, there have only been four documented families that show this disease. Only one of these families shows adermatoglyphia in isolation, with no other symptoms. The primary research article published in The American Journal of Human Genetics primarily used linkage analyses, sequencing, HeLa cell transfection, and RT-PCR to locate and characterize the gene believed to be responsible. (Nousbeck et al., 2011).


To begin, the scientists used novel sequencing technology to look at several sections of the family members’ genomes. The sections the researchers targeted were SNPs, small DNA markers which tend to be unique to each individual. By comparing which inherited SNPs most often coincided with adermatoglyphia, the researchers could narrow the search down to a particular region of chromosome 4. This region had the highest LOD score or “log of ods.” A LOD score close to 3 tends to indicate extreme proximity to the gene of interest. By sequencing this region in each family member, the researchers were able to narrow the window down to seventeen genes. Using PCR, they discovered that one isoform or splice version of a gene called SMARCAD1 had a single nucleotide transversion in the afflicted individuals. Most of the time, SMARCAD1 works fine since the most commonly expressed form splices out the mutated region. The isoform that appears in skin, however, utilizes the mutated region as what is called a cryptic donor splice site which the researchers believed to result in a loss of function when an intron inadvertently remains in the transcript. Since this isoform is primarily expressed in skin fibroblasts, the researchers decided to test SMARCAD1 as it was the most likely candidate (Nousbeck et al., 2011).


Nousbeck and his team transformed a genetic construct containing the mutated form of SMARCAD1 into HeLa cells, a human laboratory cell line. In addition, they transformed the wildtype SMARCAD1 into HeLa cells as a control. Following RT-PCR of these expressive HeLa lines, the researchers found fragments of DNA of a length not found in the control group. These lengths mirrored the PCR-RFLP analysis the research group did of the family in question (Nousbeck et al., 2011).

Comparison

New York Times

This article establishes the tone with the title of “No Prints?, Evidence Points to Mutated Gene.” The title carefully dodges a common trope of genetic popular news articles that too often read “the gene for (insert disease) discovered.” After all, the absence or mutation of the correctly functioning allele of the gene is usually what is responsible for the disease, not the gene itself (Bhanoo, 2011).


Following the title, the article’s perspective zooms out about as far as it can go and talks about fingerprints themselves. In this way, the author tries to explain this subject to an audience that may not even know that fingerprints are entirely unique to each individual. Then, the article goes on to name the disease associated with no fingerprints. Essentially, the opening paragraph can be broken down to these points:

To say that the research team found the mutation that causes the disease is a slight overstatement. According to Kua et al. (2004), the problem here is lack of qualifiers and generalized overstatement. Sindya Bhanoo, the author of the New York Times article, omits several important facets of the discovery in question. For starters, the researchers have strong evidence that the mutation of the gene causes the observed affliction, but “have identified the gene mutation that causes the disease” (Bhanoo, 2011) lacks the qualifiers and suggests a certainty also found in the primary research article. In addition, it may be premature to say that all adermatoglyphia can be associated with this mutation. As stated in the primary research, abnormal fingerprints are often a symptom of other diseases (Nousbeck et al., 2011). The mutation the researchers discovered certainly appears to be the culprit for this family’s adermatoglyphia, but the research team has not yet found this mutation in the other three families displaying the disease. In fact, because those families also show skin blistering and other symptoms, they probably have a different mutation.


The New York Times article goes on to explain which gene was identified by the researchers (SMARCAD1). Bhanoo explains that the mutation is only a problem in one isoform of the gene which she is careful to define. In fact, she includes a small allusion to an anecdote that is absent from the primary research. Apparently, the Swiss family in the research was identified when one of the family members had difficulty in immigration due to lack of fingerprints. This small story helps humanize the piece and distinguish it from the primary research article which is more focused on the facts of the disease and its cause. She concludes with a remark from Sprecher which is appropriately tempered. He does not say that he found the gene responsible for fingerprints. Instead, he says he found “an element vital to form fingerprints” (Bhanoo, 2011).

BBC

Interestingly, the BBC news article identifies Dr. Sprecher as well, but not until further down the page. Instead, the article, with no attributed author, uses the nebulous “scientists believe” and “researchers said.” There is nothing particularly wrong about this (look further up the page to see me doing the same thing), but it does make the story more impersonal and distributes agency. It appears as though the science community and researchers in general act as a kind of hive-mind rather than individuals performing tests at their own discretion (BBC, 2011).


The BBC article then focuses its attention on the Swiss family at the center of the experiments and their absence of fingerprints before identifying the SMARCAD1 gene in particular. Here, the author slips in a factoid absent from the New York Times article that was present in the primary research article. Adermatoglyphia is often referred to as “immigration delay disease” (Nousbeck et al., 2011). This title is somewhat humorous but suggests the story mentioned at the end of the New York Times article without humanizing it (BBC, 2011).


The article goes on to talk about versions of the gene without using the word “isoforms.” This decision not to include the term may be to avoid confusion for the reader and the extra burden of a correct explanation. However, the article does say that SMARCAD1 is thought to control activity of other genes, a key piece of information remarkably absent from the New York Times piece. The article concludes with a statement from Dr. Sprecher as the New York Times one did (BBC, 2011).

Conclusions

Both articles leave much of the methodology of the primary research article absent despite the simplicity of some of the assays and experiments. For example, the HeLa cell transformations could have given readers some insight into how mutations in target genes are confirmed or not confirmed as culprits for a disease. A simple statement saying that the researchers had placed mutated and wildtype versions of the SMARCAD1 gene in laboratory cell lines to confirm SMARCAD1 as the culprit gene would have sufficed. Instead, the way the information is presented, the reader is forced to accept the conclusions without any of the evidence. Both articles omit laboratory methodology for the sake of clarity. This is not always a worthy tradeoff according to Kua et al. (2004).

In addition, the New York Times article fails to place this discovery within a larger body of scientific understanding. It is interesting that a mutation resulting in the loss of fingerprints was discovered, but it is also important that this research represents some of the first characterization of a gene that may be vital to development but about which little is known. BBC does a better job than the Bhanoo article in this regard when it quotes Sprecher saying that "Little is known about the function of full-length SMARCAD1 and virtually nothing regarding the physiological role of the skin-specific version of the gene" (BBC, 2011).

Translation of primary research articles into popular media stories is a difficult task. Both popular news articles omit methodology and other aspects of the discovery that might have taken only a few more sentences to expound and clarify. In fact, both articles leave out some interesting aspects of the primary research article that are jargon-free and might be interesting to the site's readership. For example, current research suggests that epidermal ridges are not important for grip but instead play a role in vibration sensing for fine texture perception (Nousbeck et al. 2011). Scientific reporting in popular news media has come a long way but the task of translating primary research still requires careful planning and editing if we are to become a more research literate society.

Eunice Kua, Michael Reder, and Martha J. Grossel. 2004. Science in the News: A Study of Reporting Genomics. Public Understanding of Science. 13: 309–322.

Sindya Bhanoo. 5 August 2011. No Prints? Evidence Points to Mutated Gene. NYTimes.com. New York Times.

Janna Nousbeck et al. 4 August 2011. A Mutation in a Skin-Specific Isoform of SMARCAD1 Causes Autosomal-Dominant Adermatoglyphia. American Journal of Human Genetics. Vol. 89, 2:302-307

BBC Health News. 4 August 2011. Scientists Find 'No Fingerprint' Gene Mutation. BBC.co.uk.

 


Shuman Home Page

Genomics Front Page

Return To Biology Course Materials

Davidson College Biology Department


 


© Copyright 2012 Department of Biology, Davidson College, Davidson, NC 28036
Send comments, questions, and suggestions to: toshuman@davidson.edu