Transforming Growth Factor-B Receptor Type - Essay Example

?10% – Is the a true representation of the experimental findings of the paper and are there constraints or limitations of the stated conclusions? The abstract of the paper on ‘Int7G24A Variant of Transforming Growth Factor-B Receptor Type is Associated with Invasive Breast Cancer’ summarizes the objective of the study, the methodology followed, the observations of the study and the conclusions made. The 234 word abstract could ideally represent the findings of the paper. The major findings done by the research are that TGFBR1 gene is associated with invasive and metastatic breast cancer and this “intronic variant may contribute to breast cancer progression”. These results have been expressed quite clearly in the abstract. It gives a clear idea to the reader on the key area of research. Most of the keywords referring to the areas of research dealt in the paper have been included in the abstract. This contributes to the process of literature review. Moreover, this will also ensure that electronic scanning of the document fetches desired results. This becomes more important as this research paper does not have a separate section on keywords. The objective of the study and the background research on the subject also has been referred in the abstract. The finding that an intronic variant (Int7G24A) ofTGF-h receptor type I (TGFBR1) is involved with bladder and kidney cancer has been used in the present study. As this is mentioned in the abstract, the background of the research becomes scientifically supported. It includes within its contents, the hypothesis of the study. In totality, the abstract of the given paper serves as a real representation of the research study. A limitation with the precision of the results is that the sample size is too less. However, the conclusions made by the paper are an ideal reference material for further research in the area. 10% (Introduction and Hypothesis)- Can you identify the experimental hypothesis (or determine if there is one) and critically analyze its “testability”? The experimental hypothesis of the study is that intronic variant (Int7G24A) of TGF-h receptor type I (TGFBR1) is involved in development and progression of breast cancer. The fact that the hypothesis has been clearly indicated in the abstract itself makes it identifiable. The testability of the hypothesis is supported by the background research done in the same area. The author has done extensive literature review to form the foundation of this research. Thus the initial conception of the thesis has been done on the basis of these scientific evidences. The findings of earlier studies on the current subject of research (germline variant is an important genetic marker as far as metastatic breast cancers are concerned) has been used by the researcher to conceptualize the hypothesis. Another key point which would determine the scientific effectiveness of a hypothesis is the capacity to bring out analyzable results. As the study analyzed specimen tissue from all the members of the sample population using tested and calibrated scientific measurements, it could quantify observations into analyzable forms. Samples were also taken from 153 non cancer female controls serving as the reference information to analyze the data. Having included these provisions, the hypothesis can be concluded as testable. Having followed these basic testability principles, the experimental hypothesis used in the study is scientifically valid. 20% (Materials and Methods) – Is there sufficient detail in the materials and methods section for you to repeat the experiments and do the proposed experiments address the hypothesis? What information is missing? A detailed record of the subjects has been explained in the paper. The sample history has been mentioned in the chapter. It has been stated that paraffin-embedded surgical specimens of patients were retrieved from the archives of the tissue bank at Wood Hudson Cancer Research Laboratory. These samples ranged from 10 to 20 years old. This information is vital for further research on the subject as this may affect the observations. The geographic location of the patients from which the samples were collected also has been recorded by the author. This is also important as the ethnic history of the patients would be influential in the study. The age and other ethnic details have been availed from Kentucky Tumor Registry. When the experiment is to be replicated these information can be further retrieved from the same source and be compared with the new results. However, the ethnic information of the patients from whom the control sample was collected has not been refereed to. As these samples were originally removed from non-cancer patients during surgery, the information on ethnic background was not available. The sample extraction processes used for sampling has also been mentioned. However, this information is not available with reference to individual samples. This is a limitation in the sample information for replicating the experiment. The author has included detailed sequenced order of the methodology followed. The process which were involved in the methodology are 1) Isolation of DNA from paraffin-embedded tissues 2) Annealing control primer-PCR-RFLP 3) PCR and single-strand conformational polymorphism and 4) DNA sequencing. For a researcher who is planning to utilize this study as background information for further research, information on every step of the methodology followed is available in the paper. However, a limitation pertaining to the methodology followed is that this has not been supported by literature review. There is no reference to prior research done standardizing this methodology. This poses questions on the scientific credibility of the processes followed. However, there are two references supporting the processes followed in PCR and single-strand conformational polymorphism. In totality, the methodology followed has resulted in quantifiable observations which could be analyzed so as to test the hypothesis. Simply put, the materials and methods were effective in scientifically testing the hypothesis. 40% (Experimental results)- Are the appropriate experimental controls included in the results and are the results presented in a logical format? Are there enough replicates and experimental repeats? Are the experimental results described appropriately? One major limitation of the study is the inappropriate sample size used. Samples were collected from 223 cases with a diagnosis of ductal carcinoma in situ (DCIS), infiltrating ductal carcinoma (IDC)/infiltrating lobular carcinoma (ILC), and metastatic breast cancer. Samples from 153 non cancer females were used as sample. This sample size is too small to test a hypothesis which covered a diverse area of medical biotechnology. Thus in terms of size, the sample size does not become representative of the sample population. This would lead to increased possibility of errors in the statistical analysis. This must be read together with the fact that the research statistically considered 95% confidence intervals. However, the author has mentioned this limitation in the paper and has suggested considering increased sample size in further researches. The samples belonged to people ranging from Afro Americans to Caucasians. However, there is no record of the geographic locations of the patients from which Nontumur control specimens were collected. This variation in the ethnic identity of the sample population in comparison with the control population would have affected the results. Resultant of this variation in the ethnic identity of control and sample is a non-representative sample population. The observations have been logically arranged to form the results of the study. The author has analyzed the data on the basis of two broader classifications which include; Int7G24A allele of TGFBR1 in breast cancer patients and non cancer controls and; Somatic mutation of the TGFBR1 gene in an invasive breast cancer. The data is thus of a quantitative nature. The author has included the images of PCR analysis which are self explanatory. Moreover, these images provide authenticity to the results. Annealing control primer-PCR techniques were applied to improve the quality of amplification. This has contributed to the precision in data. The data evolved out of the research has been logically used to test the hypothesis and present the conclusion of the research. Statistically insignificant observations have been excluded from analysis. The case of patients with invasive breast cancer had higher frequency of TGFBR1*6A allele, where the difference between control and sample population was not statistically significant is one of the examples for this. This adds precision to the result. In totality, the results presented after analysis has been scientific. 20% (Discussion and Conclusions) - Do the experimental results support the conclusions reached by the authors in the discussion? Is their reference to other authors’ work quoted and interpreted appropriately in the discussion? Please provide examples to support your critique and quote reference material from the original article to support your analysis if possible. The author has done extensive literature review in order to support the arguments that the research is putting forward. 23 different existing works has been quoted by the author to interpret the observations of the study. The quality and the relevance of the reference material used is also a critical factor determining the precision of the results. In the discussion chapter, the author has used research papers published in 2005, which is just a year behind the year of the discussed work. Most of the references used are peer reviewed articles. The time range of these articles is spread from 1991 to 2005. The author has effectively used these works to substantiate the observations made out of the research. An example for this is the observation on somatic mutations in nine exons of the TGFBR1 gene, which was very similar to the observation made by ChenT, Carter D, Garrigue-Antar L and Reiss M (1998) in their research on ‘Transforming growth factor h type I receptor kinasemutant associated with metastatic breast cancer’. Read More