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In This Article
 »  Abstract
 » Introduction
 »  Materials and Me...
 » Results
 » Discussion
 » Conclusion
 » Annexure 1
 »  References
 »  Article Figures
 »  Article Tables

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 Table of Contents    
RESEARCH ARTICLE
Year : 2021  |  Volume : 53  |  Issue : 1  |  Page : 19-24
 

Students' knowledge and views on pharmacogenomic education in the medical curriculum


1 Department of Pharmacology, Pt. J N M Medical College, Raipur, Chhattisgarh, India
2 Demonstrator, Department of Pharmacology, Maharaja Jitendra Narayan Medical College & Hospital, Coochbehar, West Bengal, India
3 Department of Pharmacology, Sri Aurobindo Institute of Medical Sciences Indore, Mathya Pradesh, India

Date of Submission06-Aug-2019
Date of Decision27-Dec-2019
Date of Acceptance27-Mar-2021
Date of Web Publication28-Apr-2021

Correspondence Address:
Dr. Manju Agrawal
Department of Pharmacology, Pt. J N M Medical College, Raipur, Chhattisgarh
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/ijp.IJP_495_19

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 » Abstract 


INTRODUCTION: Pharmacogenomics is a growing field of science that explores the genetic contributions in an individual's response to the drug, so as to choose the right drug in the right doses tailored to a patient's genetic makeup. Although pharmacogenomics information is incorporated in chapters discussing relevant drugs, it has not been materialized into clinical practice yet and still, it remains a challenge due to limited knowledge and accessibility of the pharmacogenomic tests to diagnose these polymorphisms. With this background, the objective of the study was to assess the knowledge and perception of pharmacogenomics among second-year MBBS students and to sensitize them regarding pharmacogenomics.
MATERIALS AND METHODS: A cross-sectional study was done in which 138 medical students responded to a preformed semi-structured assessment tool. It comprised two main components (1) knowledge and (2) relevance of pharmacogenomics in medical education and clinical practice.
RESULTS: Ninety-five percent students defined pharmacogenomics correctly, but only 54% were aware of genetic variations in drug targets, metabolizing enzymes, and transporters affecting drug therapy. Only 15% knew about the availability of pharmacogenomics tests in India. Eighty-four percent of students felt that incorporating pharmacogenomics education in the MBBS curriculum is a must for precision medicine.
CONCLUSION: Second-year MBBS students had good knowledge of pharmacogenomics, but knowledge about the application in clinical practice and interpretation of pharmacogenomics was limited. Therefore, we recommend (1) basic pharmacogenomic education at all levels of medical curricula, (2) development of case-based knowledge application modules, (3) regular continuing medical education to update about available screening tools/biomarkers, and (4) patient and public awareness programs so that they receive personalized/precision medicine with optimum efficacy and reduced side effects and health-care costs.


Keywords: Knowledge, medical curriculum, personalized medicine, pharmacogenomics


How to cite this article:
Agrawal M, Kirtania L, Jha A, Hishikar R. Students' knowledge and views on pharmacogenomic education in the medical curriculum. Indian J Pharmacol 2021;53:19-24

How to cite this URL:
Agrawal M, Kirtania L, Jha A, Hishikar R. Students' knowledge and views on pharmacogenomic education in the medical curriculum. Indian J Pharmacol [serial online] 2021 [cited 2021 Jul 23];53:19-24. Available from: https://www.ijp-online.com/text.asp?2021/53/1/19/315082





 » Introduction Top


Current concepts in drug therapy often attempt drug treatment of large patient populations as groups, “one size fits all” approach to drug prescription and dosing, irrespective of their individual genetic differences in drug response.[1] Approximately 25%–60% of patients respond positively to their medications, but the remaining fraction suffers from significant therapeutic delays due to pharmacogenomic variations.[2] This increases the incidence of adverse drug reactions (ADRs), which prolongs hospital stay and is the sixth leading cause of death in the world.[2],[3] Pharmacogenomics is a growing field of science that explores genetic contributions in an individual's response to drugs.[4]

Pharmacogenetics refers to “monogenetic variants” affecting drug response, whereas pharmacogenomics refers to the “entire spectrum of genes (genome)” which can influence drug efficacy and safety. However, both the terms are used interchangeably.[5] It combines the knowledge of drug pharmacokinetics and pharmacodynamics with modern genetic testing to provide a comprehensive view of the response of a particular patient to specific drug therapy. Therefore, proper education and training in this specialty will guide to practice personalized medicine to optimize drug efficacy, prevent toxicity, and reduce the overall economic burden to the health-care system.[4] The Human Genome Project in 2003 threw open the doors to pharmacogenomics exploration worldwide.[6] Delay in translating this knowledge into clinical practice relates to the fact that an individual's response to drugs is multifactorial, resulting from multiple genes and environmental interactions and nonavailability of facilities for genetic testing.[7]

Genetic variations can result from single-nucleotide polymorphism (SNP), insertion, deletion, or duplication of DNA sequences. SNP is probably the most common variation. Polymorphisms in the drug metabolizing enzymes are the first recognized and[8] clinically relevant examples are (1) Thiopurine S-methyltransferase (TPMT) -deficient patients on mercaptopurine experience severe myelosuppression and dose reduction is recommended[9] and (2) patients receiving carbamazepine who test positive for HLA-B*1502 allele are at higher risk of Steven–Johnson syndrome and toxic epidermal necrolysis.[10],[11] The United States Food and Drug Administration (FDA) further strengthen the role of pharmacogenomics in clinical practice by changing the drug labeling of drugs such as warfarin, clopidogrel, and aripiprazole requiring testing for CYP2C9, CYP2C19, and CYP2D6 polymorphism, respectively.[12],[13] Pharmacogenomics testing requirements are mentioned in more than 100 medications drug labels, such as trastuzumab, cetuximab, maraviroc, and dasatinib and “highly recommended” testing for abacavir, carbamazepine, irinotecan, and mercaptopurine.[14]

Indian population is extremely diversified by their genetic constitution, language, religion, and sociocultural characteristics. These differences make them a unique resource for pharmacogenomics heterogeneity compared to the rest of the world.[15] Chhattisgarh (Central India) population is made of multiple ethnic groups, and a study shows that G6PD deficiency varies from 13.0% to 21.3% in the Gond tribal population of this area compared to 2.3%–27.0% in India.[16] The inclusion of pharmacogenomics in health-care delivery poses many challenges: like defining candidate gene and drug, choosing relevant biomarkers, their accessibility in the stipulated time period, interpretation of results, and cost-effectiveness.[17]

Therefore, sensitizing medical students about the need of pharmacogenomics education in medical institutions is the need of the hour. In response to the growing need, various international organizations have taken the initiative to incorporate standard pharmacogenomic education in medical, pharmacy, and public health schools.[18] In 2005, the International Society of Pharmacogenomics (ISP) made recommendations for undergraduate medical teaching in pharmacogenomics.[19] With this background, we did this study to assess second-year MBBS student's knowledge and views on the importance and relevance of pharmacogenomics in the medical curriculum, with the aim to sensitize them as well as to get their views so that they can apply this evolving science into practice to optimize treatment.


 » Materials and Methods Top


Study design

A cross-sectional study design was conducted in which a structured assessment tool was used by the Department of Pharmacology, Pt J N M Medical College, Raipur.

Study period

This study was conducted in May 2017.

Sample size

The study population was second-year MBBS students. One hundred sixty students were enrolled in the class, and on the day of the data collection, 138 students were present in the class. Verbal consents were obtained, and those unwilling to participate in the survey were given the option not to participate, but all 138 students consented to participate. The purpose of this study was explained, and they were instructed to answer questions sincerely. Confidentiality was assured. The assessment tool was filled in the presence of departmental faculty.

Data collection tool

A preformed, semi-structured questionnaire based on our study objectives was developed based on the previous literature[14],[17],[19],[20] and reviewed by departmental faculty. It was pilot tested among the postgraduate students of the department and subsequently modified. The final questionnaire consisted of 20 questions: question no 2 was open ended and the remaining were closed ended. Closed-ended questions were on 3-point Likert scale format, and it took 20 min to fill the questionnaire [Annexure 1].

Statistical analysis

Statistical analysis was done using descriptive statistics and nonparametric test (Chi-square test) for proportionality using IBM SPSS version 20 IBM Director of Licensing, IBM Corporation, North Castle Drive, Armonk, NY 10504-1785, U.S.A.

Ethical Justification

The Institutional Ethics Committee permission was obtained prior to the initiation of the study.


 » Results Top


All 138 students had completed and returned the questionnaires of which 110 students had heard about pharmacogenetics/genomics and were included in the study, 59% were male and 41% were female. In terms of gender, the knowledge and relevance scores were statistically not significant (P > 0.5). A majority (80%) of the students had heard the words pharmacogenomics and personalized medicine from textbooks and the Internet [Figure 1]. Fifty-four percent of students defined pharmacogenomics and personalized medicine correctly.
Figure 1: Source of pharmacogenomics information

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In response to questions on Knowledge of pharmacogenomics [Table 1] 95% of students knew that pharmacogenomics is the study of drug response in relation to human genetic variations and 90% understood its role in drug safety, but only 54% of students knew that genetic variations in drug targets, metabolizing enzymes, and transporters affect drug therapy. Only 43% had knowledge about the relation of responsiveness of trastuzumab and human epidermal growth factor receptor 2 (HER2) receptor and 40% knew that genetic variations affect the toxicity of isoniazid. Eighty prercent of students knew that genetic variations influence the incidence of hemolytic anemia in G6PD-deficient people.
Table 1: Knowledge of pharmacogenomics

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When asked about the relation of pharmacogenomics to pharmacovigilance and drug development, 46% said that knowledge of pharmacogenomics is likely to decrease the number of ADR and 68% had no idea if pharmacogenomics would decrease the cost of developing drugs, as shown in [Table 2]. Student's opinions were taken on the relevance of knowledge of pharmacogenomics where 84% thought that pharmacogenomics is relevant to the medical profession and 82% wanted it to be included in the MBBS curriculum. Ninety-three percent felt that it is relevant in patients' diagnosis and treatment and 84% felt that it should be linked to the pharmacovigilance program to reduce ADRs. Eighty-one percent of students said that pharmacogenomic testing is not for sick people only and 47% thought that using pharmacogenomics in practice will increase health-care costs [Table 2]. Almost 82% of respondents had no idea about the availability of pharmacogenomics testing in India [Figure 2]. Only 68% were willing to have their own pharmacogenomics profile. Only 58% of students know that genetic information is now a requirement for some drug labels, according to the FDA [Figure 3]. Test for proportionality has been applied to check if there is any statistical difference between correct and incorrect responses for knowledge and relevance. Test for proportionality had been applied and it was observed that statistically significant number of students had adequate information regarding pharmacogenomics and it's relevance and importance in health care.
Figure 2: Responses on availability of pharmacogenomics testing in India

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Figure 3: Knowledge about Food and Drug Administration drug labeling

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Table 2: Importance and relevance of knowledge of pharmacogenomics

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 » Discussion Top


Most of the students have a good knowledge of pharmacogenomics and understood the relevance with a few areas of gaps. Majority of the students were unaware of the fact that pharmacogenomic variations in drug target, metabolizing enzymes, transporters affect drug therapy. Similarly, a large number of students could not relate how pharmacogenomic knowledge would help in reducing the cost of drug development and the availability of pharmacogenomic tests in India. An Internet search did not show any study in India, showing health-care students' feedback of their views on pharmacogenomics and its incorporation in medical education. Textbook followed by the Internet is the source of knowledge about pharmacogenomics. A similar study done in the USA shows that only 15.9% of medical students agreed that pharmacogenomics had been a part of their curriculum,[4] whereas a study done in Ghana revealed that doctors had heard the term from colleagues followed by Internet and medical schools.[17] Fifty-four percent of students were able to define the terms pharmacogenomics and personalized medicine correctly, in spite of the fact that this topic was mentioned during the general pharmacology lectures. ISP education forum has recommended a minimum of 4 h of undergraduate pharmacogenomics teaching to medical students in 2005 by incorporating it in core pharmacology curriculum, in the education of physicians, pharmacists, and nurses to emphasize upon the significance of this rapidly evolving topic.[18] This can be incorporated as case-based learning, citing common examples of a polymorphism affecting pharmacodynamic and pharmacokinetics frequently and conducting continuing medical education (CME) in hospitals. They also called upon the publishers of pharmacology textbooks to dedicate a separate chapter on pharmacogenomics and pharmaceutical industry to develop tools for web-based learning.[21]

Maximum students could recognize the role of pharmacogenomics in drug safety which is similar to a study conducted in Malaysia where 95% of students knew that PG aims at understanding the roles of human genetic variations in drug safety.[22] Guideline for the use of pharmacogenomics in the pharmacovigilance states that “it is desirable to have data regarding relevant genomic biomarkers relating to efficacy and safety of a new medicinal product, including patient selection or dose specification at the time of approval so as to reduce ADRs.”[23] Students awareness about G6PD deficiency and resulting hemolysis is because of (a) its association with commonly used drugs such as co-trimoxazole, fluoroquinolones, dapsone, (b) endemicity of Malaria in our state and use of primaquine, and (c) high prevalence of G6PD deficiency in this area.[16] Only 5% of students felt that pharmacogenomics should not be a part of their curriculum similar to a study[4] where only 2.9% of students disagreed on this proposed curriculum expansion. They might have felt that this will increase their study burden, or they may be having a lack of confidence and awareness about the relevance of pharmacogenomics in clinical practice. In another study, 96.9% of medical doctors agreed that students should be equipped with pharmacogenomics information.[17] Majority of UK medical schools included 1–2 h of pharmacogenomic teaching in the curriculum.[14] Fifty-three percent of students felt that pharmacogenomics information is likely to decrease the number of ADRs, and this information must be linked to pharmacovigilance for better drug safety. Sixty-eight percent felt that knowledge of Pharmacogenomics will decrease the cost of developing drugs. In the process of drug discovery, many drugs fail to emerge as therapeutic agents due to failure of efficacy or appearance of ADR, leading to termination of clinical trial and incurring financial loss to the pharmaceutical company.

Fifty-seven percent students were aware of genetics information as a requirement for some drug labels according to the FDA, which is similar to another study.[10] As of 2018, FDA has published a table of pharmacogenomic markers in drug labeling and has 362 entries, and it describes issues such as (1) variability in clinical response, (2) risk of ADRs, (3) genotype-specific dosing, and (4) polymorphic drug disposition gene.[23] Eighty-two percent of students had no idea if pharmacogenomics screening is available in India. Pharmacogenomic screening is now available in India and provided by both government institutes and private laboratories. Some of the available tests are for SNPs related to suxamethonium, 5-fluorouracil, CYP2C9 Gene screening for warfarin and HER2/neu receptor screening for trastuzumab.[24] Students were also interested in having their own pharmacogenomics profile and would volunteer for personal pharmacogenetics testing if given an opportunity which is similar to study done by Surofchy et al where 59.8% volunteered for personal pharmacogenetic testing.[25]


 » Conclusion Top


Students had good knowledge and interest of pharmacogenomics in general, but knowledge about the application and interpretation of pharmacogenomics was limited. With scientific evolution in technology and understanding of the human genome, availability of easy to use, cost-effective, reliable to interpret tools/biomarkers will culminate this knowledge in treatment with optimum efficacy, minimum toxicity, and affordable health-care costs. Thus, we recommend (1) basic pharmacogenomic education at all levels of medical curricula, (2) development of case-based knowledge application modules, (3) regular CME to update about available screening tools/biomarkers, and (4) patient and public awareness programs so that the clinician is confident and patients assured that they are on the path of precision medicine.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.


 » Annexure 1 Top


Questionnaire

Students’ knowledge and views on pharmacogenomic education in the medical curriculum

Department of pharmacology

Pt JNM Medical College, Raipur, Chhattisgarh, India

Demographic details: age…...…. /sex…‥.

  1. Have you heard about Pharmacogenetics /Genomics / Personalised medicine? YES / NO / NO IDEA
  2. What do you understand by these terms?
  3. What is the source of your information on Pharmacogenomics? Not heard / Internet / Media / Journal / Text book / Lecture


  4. KNOWLEDGE ABOUT PHARMACOGENETICS:

  5. Pharmacogenomics is the study of drug response in relation to human genetic variations - YES / NO / NO IDEA
  6. Pharmacogenomics aims at understanding the role of human genetic variations in drug safety - YES / NO / NO IDEA
  7. Genetic variations in drug targets, metabolising enzymes, and transporters affect drug therapy - YES / NO / NO IDEA
  8. Trastuzumab responsiveness is due to genetic variation in HER2 receptor- YES / NO / NO IDEA
  9. Genetic variation affects pharmacological action of isoniazid- YES / NO / NO IDEA
  10. Genetic variations influence occurrence of haemolytic anaemia in G6PD deficient - YES / NO / NO IDEA


  11. RELEVANCE OF KNOWLEDGE OF PHARMACOGENOMICS

  12. Is the knowledge of Pharmacogenomics likely to decrease the number of ADRs? - YES / NO / NO IDEA
  13. Is the knowledge of Pharmacogenomics likely to decrease the cost of developing drugs? - YES / NO / NO IDEA
  14. Is Pharmacogenomics relevant to your profession - YES / NO / NO IDEA
  15. Should Pharmacogenomics information be included in your MBBS curriculum? - YES / NO / NO IDEA
  16. Should Pharmacogenomics be part of diagnosis and treatment - YES / NO / NO IDEA
  17. Do you believe that Pharmacogenomics & Pharmacovigilance be linked together for better drug safety? - YES / NO / No idea
  18. Is pharmacogenomic testing only for sick people? - YES / NO / No idea
  19. Using pharmacogenomics in practice will increase health care costs
  20. Pharmacogenomic tests are now available in India - YES / NO / NO IDEA
  21. Would you like to have your own Pharmacogenomics profile? - YES / NO / NO IDEA
  22. Genetics information is now a requirement for some drug labels, according to Food and Drug Administration (FDA) - YES / NO / NO IDEA




 
 » References Top

1.
Zhou S. Teaching of clinical pharmacogenetics for pharmacy students at the National University of Singapore. Pharm Educ 2005;5:1-6.  Back to cited text no. 1
    
2.
Yau A, Aziz AB, Haque M. Knowledge, attitude and practice concerning pharmacogenomics among pharmacists: A systematic review. J Young Pharm 2015;7:145.  Back to cited text no. 2
    
3.
Singh P, Agrawal M, Hishikar R, Joshi U, Maheshwari B, Halwai A. Adverse drug reactions at adverse drug reaction monitoring center in Raipur: Analysis of spontaneous reports during 1 year. Indian J Pharmacol 2017;49:432-7.  Back to cited text no. 3
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Moen M, Lamba J. Assessment of healthcare students' views on pharmacogenomics at the University of Minnesota. Pharmacogenomics 2012;13:1537-45.  Back to cited text no. 4
    
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DiPiro JT, Talbert RL, Yee GC, Matzke GR, Wells BG, Posey LM. Pharmacotherapy: A Pathophysiologic Approach. 9th ed. New York: McGraw-Hill Education; 2014.  Back to cited text no. 5
    
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Chial H. DNA sequencing technologies key to the Human Genome Project. Nat Edu 2008;1:219.  Back to cited text no. 6
    
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Haga SB, Burke W. Using pharmacogenetics to improve drug safety and efficacy. JAMA 2004;291:2869-71.  Back to cited text no. 7
    
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Ma Q, Lu AY. Pharmacogenetics, pharmacogenomics, and individualised medicine. Pharmacol Rev2011;63:437-59.  Back to cited text no. 8
    
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Evans WE. Pharmacogenetics of thiopurine S-methyltransferase and thiopurine therapy. Ther Drug Monit 2004;26:186-91.  Back to cited text no. 9
    
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Yau A, Husain R, Haque M. A systematic review of knowledge, attitude and practice towards pharmacogenomics among doctors. Int J Pharm Res 2015;7:9-16.  Back to cited text no. 10
    
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Mockenhaupt M, Viboud C, Dunant A, Naldi L, Halevy S, Bouwes Bavinck JN, et al. Stevens-Johnson syndrome and toxic epidermal necrolysis: Assessment of medication risks with emphasis on recently marketed drugs. The EuroSCAR-study. J Invest Dermatol 2008;128:35-44.  Back to cited text no. 11
    
12.
Formea CM, Nicholson WT, McCullough KB, Berg KD, Berg ML, Cunningham JL, et al. Development and evaluation of a pharmacogenomics educational program for pharmacists. Am J Pharm Educ 2013;77:10.  Back to cited text no. 12
    
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Food US, Drug A. Table of Pharmacogenomic Biomarkers in Drug Labeling. https://www.fda.gov/drugs/science-and-research-drugs/table-pharmacological-bio-markers-drug-labeling. [Last accessed on 2021 Apr 21].  Back to cited text no. 13
    
14.
McCullough KB, Formea CM, Berg KD, Burzynski JA, Cunningham JL, Ou NN, et al. Assessment of the pharmacogenomics educational needs of pharmacists. Am J Pharm Educ 2011;75:51.  Back to cited text no. 14
    
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Aggarwal S, Phadke SR. Medical genetics and genomic medicine in India: Current status and opportunities ahead. Mol Genet Genomic Med 2015;3:160-71.  Back to cited text no. 15
    
16.
Mukherjee MB, Colah RB, Martin S, Ghosh K. Glucose-6-phosphate dehydrogenase (G6PD) deficiency among tribal populations of India-Country scenario. Indian J Med Res 2015;141:516-20.  Back to cited text no. 16
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17.
Kudzi W, Addy BS, Dzudzor B. Knowledge of pharmacogenetics among healthcare professionals and faculty members of health training institutions in Ghana. Ghana Med J 2015;49:50-6.  Back to cited text no. 17
    
18.
Zgheib NK, Ghaddar F, Sabra R. Teaching pharmacogenetics in low and middle-income countries: Team based learning and lessons learned at the American University of Beirut. Curr Pharmacogenomic Per Med 2011;9:25-40.  Back to cited text no. 18
    
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Higgs JE, Andrews J, Gurwitz D, Payne K, Newman W. Pharmacogenetics education in British Medical Schools. Genomic Med 2008;2:101-5.  Back to cited text no. 19
    
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Yau A, Husain R, Abd Aziz A, Zahri Johari MK, Rahman AF, Elkalmi RM, et al. Psychometric properties of knowledge, attitude, and practice on pharmacogenovigilance in drug safety questionnaire in medicine and pharmacy students: Based on Exploratory Factor Analysis. J Appl Pharm Sci 2015;5:15-22.  Back to cited text no. 20
    
21.
Gurwitz D, Lunshof JE, Dedoussis G, Flordellis CS, Fuhr U, Kirchheiner J, et al. Pharmacogenomics education: International Society of Pharmacogenomics Recommendations for Medical, Pharmaceutical, and Health Schools Deans of Education. Pharmacogenomics J 2005;5:221-5.  Back to cited text no. 21
    
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Yau A, Haque M. Pharmacogenomics: Knowledge, attitude and practice among future doctors and pharmacists-A pilot study. J Appl Pharm Sci 2016;6:141-5.  Back to cited text no. 22
    
23.
Guideline on key aspects for the use of pharmacogenomics in the pharmacovigilance of medicinal products. EMA/CHMP/281371/2013. Accessed April21, 2021.  Back to cited text no. 23
    
24.
Go Med Genomics and Other Omics Tools for Enabling Medical Decision. CSIR-Institute of Genomics and Integrative Biology. Available from: http://gomed.igib.in/. [Last assessed on 2019 Mar 03].  Back to cited text no. 24
    
25.
Surofchy D, Oh S, Galanter J, Xiang P, Li M, Guo S, et al. Personal pharmacogenetic testing enhances pharmacy student knowledge and attitude towards precision medicine. Inov Pharm 2017;8: Article 2. doi.10.24926/21550417.1242.  Back to cited text no. 25
    


    Figures

  [Figure 1], [Figure 2], [Figure 3]
 
 
    Tables

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