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Original research
Cancer patients’ views and understanding of genome sequencing: a qualitative study
  1. Nicci Bartley1,
  2. Megan Best1,
  3. Chris Jacobs2,
  4. Ilona Juraskova1,
  5. Ainsley J Newson3,
  6. Jacqueline Savard4,
  7. Bettina Meiser5,
  8. Mandy L Ballinger6,
  9. David M Thomas6,
  10. Barbara Biesecker7,
  11. Phyllis Butow1
  1. 1 School of Psychology, Faculty of Science, The University of Sydney, Camperdown, New South Wales, Australia
  2. 2 Graduate School of Health, University of Technology Sydney, Sydney, New South Wales, Australia
  3. 3 School of Public Health, Faculty of Medicine and Health, The University of Sydney, Sydney, New South Wales, Australia
  4. 4 School of Medicine, Faculty of Health, Deakin University, Burwood, Victoria, Australia
  5. 5 Prince of Wales Clinical School, University of New South Wales Sydney, Sydney, New South Wales, Australia
  6. 6 The Kinghorn Cancer Center and Garvan Institute of Medical Research, Darlinghurst, New South Wales, Australia
  7. 7 Research Triangle Institute, Research Triangle Park, North Carolina, USA
  1. Correspondence to Nicci Bartley, School of Psychology, Faculty of Science, The University of Sydney, Camperdown, NSW 2006, Australia; nicole.bartley{at}


Background Little is known about knowledge of, and attitudes towards, genome sequencing (GS) among individuals with a personal history of cancer who decide to undergo GS. This qualitative study aimed to investigate baseline knowledge and attitudes among individuals previously diagnosed with a cancer of likely genetic origin who have consented to GS.

Methods Semistructured interviews were conducted with purposively selected participants (n=20) from the longitudinal Psychosocial Issues in Genomic Oncology study, within a month of consenting to GS and prior to receiving any results. Participants were adults with a cancer of likely genetic aetiology who are undertaking GS as part of a larger genetic study.

Results Analysis identified three main themes: limited understanding of genomics; multifactorial motivation; and complex decision making. While motivations such as obtaining health information about self and family appear to be the main drivers for undertaking GS, these motivations are sometimes based on limited knowledge of the accuracy and utility of GS, creating unrealistic expectations. This in turn can prolong the deliberation process and lead to ongoing decisional conflict.

Conclusion Understanding the degree and nature of patient understanding of GS, as well as their attitudes and decision-making processes, will enable healthcare professionals to better manage patient expectations and appropriately engage and support patients to make an informed decision when pursuing GS.

  • cancer
  • genome sequencing
  • patient attitudes
  • psychosocial
  • qualitative

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In 2018, there were an estimated 18.1 million new cases of cancer worldwide.1 The heritable contribution to cancer has traditionally been estimated at 5%–10%,2 but recent data indicate it may be much greater.3 An early onset of cancer (diagnosis under 40 years), multiple primary cancer diagnoses and/or a family history of cancer are examples of features of a likely heritable genetic aetiology.2

Genome sequencing (GS) ascertains the complete DNA sequence of the genome (~23 000 genes in humans).4 The capacity to simultaneously analyse multiple genes has the potential to impact cancer clinical care through the generation of unprecedented amounts of information about an individual and their blood relatives.5 6 Individuals previously diagnosed with cancer who undergo GS may receive information that: (1) is relevant to the target cancer, with or without proven risk management or treatment strategies; (2) is relevant to other cancers or diseases (secondary findings), with or without proven risk management or treatment strategies; or (3) is of unknown significance.7 This broad scope means that patients necessarily engage with more than condition-specific information.8 9

GS may soon be an acceptable and cost-effective clinical tool for personalising cancer prevention and risk management. In an effort to address ethical concerns around informed patient decision making for GS, Aysuo and colleagues7 developed a list of minimal elements of consent to help ensure that patients are able to appreciate what GS involves and what findings it may generate. However, a recent systematic review of psychological and behavioural outcomes of cancer genomic testing highlighted that in addition to limited patient knowledge, challenges to implementing GS in cancer clinical practice include negative, or overly optimistic attitudes towards testing.10 It is important to develop empirically based strategies to address patient understanding and attitudes before GS is offered more widely.

Patient knowledge and attitudes towards individual gene testing have been well documented. High-risk individuals undertake gene testing for specific cancer conditions to protect their own health, provide information for family, reduce uncertainty and respond to requests from family members and medical providers.11–13 High-risk individuals also report concerns about personal and family impact and financial implications when deciding whether to pursue genetic testing for cancer syndromes.14

Research investigating knowledge and attitudes towards GS has focused on primary care and cardiology patients.15 16 The few studies that have investigated knowledge and attitudes among individuals with a personal history of cancer who pursue GS have been hypothetical,17–19 with very few including individuals who have actually been offered and decided to undergo GS. The aim of this study was therefore to investigate knowledge and attitudes among individuals with a personal history of cancer who have decided to pursue GS as part of a larger research study examining cancer risk.



Participants in this qualitative study were recruited from an existing Australia-wide study of adults with a cancer of likely genetic aetiology (the Genetic Cancer Risk in the Young (RisC) study). Eligibility criteria for the RisC study include features of likely genetic aetiology cancer, that is: histologically confirmed malignancy and aged 16–40 years at diagnosis, or having >1 primary cancer diagnosed <50 years of age or having >2 primary cancers at any age. Exclusion criteria include non-melanoma skin cancer diagnosis and an inability to understand the English language. The RisC study aims to recruit 1000 adults with the primary objective of identifying the number of clinically actionable pathogenic variants in the cohort.

Most RisC participants are initially offered participation in the study by their geneticist or a member of the RisC research team, with some hearing about the study from patient advocacy organisations. Participation in the RisC study involves providing a blood sample for GS. The GS takes approximately 18 months to complete, and participants will only receive results if the GS identifies important information about their health. RisC participants can choose whether they would like to be informed if they have a pathogenic variant that increases the likelihood of cancer and/or are found to have a secondary finding (according to the recommendations for reporting secondary findings in clinical exome and genome sequencing) that may be important to their health.20 RisC participants who receive an actionable result following GS are offered the opportunity for genetic counselling, and those who receive a result of a pathogenic variant that increases the likelihood of cancer will be offered tailored risk management in a subsequent study.

Psychosocial substudy (Psychosocial Issues in Genomic Oncology (PiGeOn))

Participants are invited to join the PiGeOn substudy21 when they give consent to join the RisC study. The PiGeOn study aims to explore the psychological, behavioural and ethical implications of GS. Participants in PiGeOn are asked to complete questionnaires at three time points (baseline, and 3 months and 12 months after consent). A subset of participants, purposively sampled to include a diversity of cancer types and demographics, are also invited to participate in a semistructured interview at each time-point. This paper reports on findings from baseline interviews that were conducted within a month of participants enrolling onto the RisC study and having blood samples taken for GS.

PiGeOn qualitative study methods

Qualitative semistructured telephone interviews were conducted by a trained qualitative interviewer (NB). The interview guide development was informed by existing literature12 13 22 and input from a multidisciplinary expert advisory group and consumers. An initial draft was pilot-tested with consumers. The interview questions, iteratively modified over the course of the study, addressed: participant knowledge of and previous experience with GS, perceived benefits and drawbacks of GS and motivation for undertaking GS (box 1).

Box 1

Interview schedule

Tell me a bit about yourself. How did you come to know about the study?

Can you tell me what you know, if anything, about the blood test you had for the study to look at your genes (whole genome sequencing)?

Had you heard about whole genome sequencing before the study? Have you had any previous experience of genetic testing before this study?

Why do you think you were offered this test?

Whole genome sequencing is a blood test which involves mapping all your genes in one test, to look for gene variants. What do you think of that/Do you understand what that means?

What do you see as the benefits, if any, of whole genome sequencing?

What worries you about it?

Why did you decide to participate?

I see from your consent form that you decided to receive X (ie, all genetic information with medical relevance, cancer actionable information only) results. Can you tell me why you made that decision?

Is there anything else you would like to say about whole genome sequencing? Do you have any advice about how this topic should be discussed with other people?

Recruitment to the qualitative study continued until data saturation (no new themes emerging after three consecutive interviews) was reached. Participants’ demographic and disease characteristics were extracted from PiGeOn questionnaires.

Data analysis

Interviews were audio recorded, transcribed verbatim and subjected to thematic analysis.23 Line-by-line coding was conducted on an initial six transcripts by the multidisciplinary (genetics, medicine, bioethics and psychology) research team. The preliminary thematic map was then applied to additional transcripts and further developed through an iterative process of review of subsequent transcripts by the research team. Differences in researcher interpretation of the data were resolved through discussion. The multidisciplinary nature of the research team minimised researcher bias regarding the meaning of the results.24


Twenty participants with diverse cancers were interviewed between August 2017 and May 2018. Interviews lasted on average 28 min. Participants’ current ages ranged from 32 years to 78 years; 65% were female; time since most recent diagnosis ranged from 3 months to 26 years; and two participants were on treatment at the time they were interviewed (table 1). There were no differences in interviewee responses based on these demographic or clinical variables.

Table 1

Participant characteristics (n=20)

Three main themes developed from the thematic analysis: (1) limited understanding of genomics; (2) multifactorial motivation; and (3) complex decision making.

Limited understanding of genomics

Most (85%) participants acknowledged that they did not fully understand or were uncertain about what GS is and the types of information that GS provides.

[Laughs] I don’t know anything about it [GS]. Participant 19: male, 78 years

Some participants mentioned rereading the study information pack and requested information or asked for reassurances during the interview, implying that they would like to better understand GS.

And then I guess I went home and just read, like the documents that she gave me in a little bit more detail… it wasn’t until I read the documentation that I was given that I, that yeah there were so many more other, other parts of your DNA that can be tested. P12: female, 39 years

Oh no, not really, I just understand that your, you know, what you call ‘em, your DNA, whatever it is, and looks for any abnormalities I suppose, does it? P20: male, 63 years

Only three participants (15%) reported a good understanding or were more confident of their understanding of GS.

Education and experience provide a foundation for understanding

Basic pre-enrolment genomic education was provided as part of the consent process to the RisC study, and some participants had undergone previous genetic testing and/or genetic counselling for specific pathogenic variants or syndromes during their cancer journey prior to joining the RisC study. Previous experience with genetic counselling or genetic testing appeared to influence participant knowledge, and participants saw the RisC study as continuing to add to their bank of genetic knowledge. Career experience and education in the sciences and/or medicine also appeared to influence understanding of GS. Only three participants self-reported working in a medical and/or science field, with these three being the only participants to clearly and confidently communicate their understanding of GS.

My understanding is that they will take the blood test to extract DNA and, basically, sequence the entirety of the code that is my DNA and look for mutations in other structural areas that may be, that may predispose or have caused my cancer. P10: male, 35 years

Previous experiences with genetic testing and/or having scientific/medical background helped participants be aware of the limitations of science, which in turn seemed to inform participants’ expectations of the (un)likelihood of receiving results. Others held more unrealistic expectations regarding the types of information that they would receive and perceived their GS as comprehensive and likely to provide them with information about their current or future health.

I guess it’s whole genome sequencing… I guess if there is something, the chances are high that they’ll pick it up. P4: female, 37 years

Multifactorial motivation

Desire and easy to participate

Overall, participants felt grateful for being offered the opportunity to have GS for no financial cost. Some participants stated they were interested in GS prior to participating in the RisC study. Highlighting expense as a barrier for pursuing GS privately, these participants expressed frustration that GS was not more widely available or accessible earlier in their cancer journey. Undertaking GS in this research context was seen as simple and easy, especially in a population who are used to medical procedures and could have this blood test done while at an existing appointment.

All I have to do is supply the blood… it’s not hard to participate… you guys are doing all the work. P6: male, 47 years


All participants were motivated to participate in the RisC study as a way of contributing to science, noting that their own experience with cancer highlighted to them the limited understanding of cancer causes and effective treatments. They hoped their participation would assist with cancer diagnosis and treatment in the future so that others, especially young people, would not have to experience the trauma they had. Due to their rare cancer diagnosis, young age of diagnosis, multiple cancer diagnoses and/or unusual response to treatment, participants saw themselves as cases of interest to science and that they were making an important scientific contribution.

Being an unexpected mutation might make me more interesting as a participant, with quite an aggressive cancer as well… I feel really grateful that everyone else who’s had cancer has been sort of guinea pigs along the way to make treatment as good as you can get it, and I sort of want to be able to be helpful as well and help improve outcomes for people coming after me. P4: female, 37 years

Familial responsibility

The majority of participants were motivated by a sense of responsibility to their family. For some participants with children, undertaking GS was seen as a parental responsibility. These participants saw GS as one method of attaining health information that would help them to make choices that in turn would help them to remain alive as long as possible for their children. A few participants were interested in obtaining GS information to inform their family planning decisions.

Most participants viewed having GS as a way of educating their family and arming siblings and the next generation with information about potential health risks for cancer and/or other diseases. Informing one’s family of their potential risk was perceived by participants as providing relatives with control over their own health and allowing them to engage in risk management that would give them a chance for better health outcomes.

I just think for the future of all the grandchildren and all the other siblings in the family, it is a good idea for us to have an idea of if we know there is some type of gene, then they can be tested, to try and maybe prevent it. P5: female, 42 years

Some participants mentioned that their family members had expressed an interest in the participant having GS to inform the family member about their own risk of cancer. Some participants were also motivated to undertake GS as a way of determining if their cancer and other cancer(s) in their family were genetically linked, rather than being ‘unlucky’.


All participants were motivated to undertake GS by curiosity about their own genes. Due to a young age of diagnosis, strong family history or atypical diagnosis, participants had long suspected that their cancer was genetic rather than environmental and considered GS as a method of confirming this. Having already experienced a major illness, participants were also curious about their future health, both in terms of chance of recurrence and anything else that may lie in their genes.

It gives you information around your genetic makeup and susceptibility maybe… you can't help but wonder, are there any other issues that you have in your body or part of your DNA that, you know the likelihood or the risk of contracting some kind of different form of cancer, or whatever later on in life, or even other diseases… Like I'd like to know if there is anything. P12: female, 39 years

Curiosity of others, such as family members and health professionals, was also noted by participants who had additional unexplained medical issues.

[My geneticist] would like to know what is causing these lumps. P19: male, 78 years


A desire for control over future health was another motivation for undergoing GS. Information was seen as empowering—the more knowledge, the better. Participants expressed hope that genomic information would give them the opportunity to prepare for future cancer or other illness, either by providing a chance for prevention through lifestyle changes or improving outcomes through screening and early diagnosis.

[I]t’s a little bit like providing… a scientific crystal ball and it’s not going to necessarily be correct and it might not come to fruition, but it’s a bit like going to a psychic… that goes, look this is possibly in your path, and you can maybe, maybe you could do something to avoid it. P3: female, 41 years

Participants viewed information gained from GS as a resource that could be used by other health professionals in the case of a cancer recurrence, potentially informing treatment options.

Reduce uncertainty

Some participants hoped that genomic information would release them from the uncertainty they were experiencing related to their current or future illnesses. These participants considered genomic information concrete, definitive, explanatory, specific to the individual and their family and that it would provide them with an actionable plan. Despite the consent process highlighting that only results with medical significance, and not results of uncertain significance would be provided in this study, most participants saw their potential result/no result as conclusive.

There’s a lot of uncertainty about my own health which causes its own issues… I don’t know what my chances of recurrence are for that, but I also don’t know what my chances are for other things… I decided that I would rather know and deal with the consequences as they come than not know and deal with the uncertainty of what I don’t know. P9: male, 37 years

Complex decision making

Deliberation process

Some participants delayed their decision to undergo GS. Reasons for postponing the decision included: not wanting to make the decision lightly as the potential outcomes of having GS could have financial or psychosocial consequences for themselves and their family; not wanting to think about ‘memories’ of their cancer and treatment; and competing life priorities (eg, death of family members and child’s cancer diagnosis).

I sort of had a quick flick through and went, whoa, okay, this is pretty deep stuff to be able to contemplate, whether you’re signing up for a terminal diagnosis, it’s not something you take lightly, and yeah, need a bit of time to think that through. P3: female, 41 years

When deciding to undertake GS, participants weighed up their motivations and concerns. While their views were not always accurate, participants were concerned about possible discrimination regarding personal insurance products and employment. Participants were uncertain how genomic results would impact their own or family members’ ability to affordably attain health related insurance products, and they worried that future changes in legislation would impact their current protection.

[I]f… the situation [results] affected my ability to get insurance in the future or affected my current insurance or any future insurance… I would say no to receiving information. P1: female, 43 years

Additionally, participants acknowledged that if the GS returned information that is important to their health, this might have a negative impact on the mental and physical health of themselves and family members, stating that genomic information might be overwhelming if provided out of context, potentially increasing uncertainty and stress.

Ultimately, the motivations for undergoing genomic testing, such as curiosity, familial obligation and empowerment, overruled concerns felt by the participants. They also reasoned that the test was not to be feared, as the pathogenic variant was there whether one knew about it or not. In general, participants felt it was better to know and be prepared than not to know.

The defect or the mutation or the cancer was already there… the test isn’t the problem, the test shouldn’t be the scary thing, it’s just giving you more information for how you can look after yourself. P4: female, 37 years

Additionally, due to their previous experience with cancer and/or genetic testing, some participants considered themselves pragmatic and resilient enough to cope with results.

I feel like I’m probably psychologically resilient enough to handle the absence or addition of information in that particular space. P10: male, 35 years

Decisional conflict

Only one participant was unsure when consenting to undergo GS about receiving both cancer-related and secondary findings. All other participants indicated at that time that they would like to receive both cancer-related and secondary findings. While satisfied with their decision to undergo GS to help science, some participants did experience decisional conflict about which type of results (if any) they would prefer to receive, indicating that the option to change their decision over the duration of the study was why they had agreed to receive all results at the point of consent to the study.

I’ve sort of been grappling with the extent to which I want to know any risks that might come out of this, the testing, to my family and myself really. And whether I want to know all the risks or whether only those life-threatening ones, or only that pertain to me… if I get old and don’t want to keep going with it… then I can just say, ‘No, I don’t want to know’. P16: male, 58 years


This study provides valuable insight into the level of GS understanding among individuals with a likely genetic aetiology of their cancer, as well as their motivations, concerns and decision-making processes when pursuing GS. Our results echo those reported in slightly different populations and contexts,25 26 and informed consent/return of results,27 supporting the generalisability and reproducibility of these themes. Regardless of their understanding of GS, participants were motivated to pursue this testing by a desire to help others, familial responsibility, curiosity and empowerment and to reduce uncertainty about their illness. For some, decision making to pursue GS required time to process motivations and to weigh up perceived benefits against any concerns, within the context of the individual’s emotional readiness to revisit their cancer risk.

Consistent with research investigating genomic knowledge in different clinical populations,15 16 28 the majority of participants in this study had limited knowledge of GS. Those who had previous experience with genetic counselling or genetic tests, and/or who had a scientific or medical background, appeared to have a clearer and more confident understanding. This supports Lea and colleagues’29 conclusion that health literacy and numeracy is an important predictor of understanding genomic information. Improved knowledge and understanding of genomics is important in mitigating individuals’ unrealistic expectations of GS,30 which is sometimes evident in their motivations for pursuing this option.

A desire to further cancer research, familial responsibility and the desire to obtain health information are the most commonly reported motivations of participants for undertaking genetic testing for specific cancer syndromes11–13 31–33 and also of at-risk individuals who undergo GS.34 35 Participants in this study reported similar motivations for pursuing GS. It is not surprising that a population with personal history of cancer, especially at a young age, would be curious about the origin of their cancer and seek information to prevent, or prepare for, future illness. It is important to note that while individuals may be motivated to undergo GS to reduce uncertainty, results such as variants of uncertain significance, or variants with no proven risk management options, also have the potential to increase uncertainty.9 It is also understandable that individuals with a personal and family history of cancer would be motivated to pursue GS by a sense of familial responsibility. However, previous research has shown that disclosure of genetic risk information can have both positive and negative impact on the individual, their relatives and their relationships.31 36 The potential discord between being motivated by a desire to provide biological relatives with useful information, and this information having negative impact on these relatives, highlights a need for family communication to begin pretesting during the decision-making process.37

There is much interest in what constitutes informed consent in genetic and genomic settings. Research has shown that while the general public have heard of basic genetic concepts, they do not understand the detailed biological mechanisms or the meaning of increased risk.38 39 Some researchers, such as Biesecker and colleagues,40 suggest that understanding the ‘gist’ of genetics may be all that is needed for some individuals making a decision to undergo genetic testing, which is supported by the participants in this study who agreed to undergo GS despite acknowledging their limited understanding of GS. Further research is needed to obtain public and ethical perspectives on the level of understanding required to constitute acceptable informed consent.

Supporting previous research on the importance of informing participants of the benefits and risks of GS during the consent process,7 this study found that when deciding to pursue GS, individuals with a personal history of cancer weigh up their perceptions of the benefits and risks of GS, but this is done in the context of their values, emotional readiness to confront their cancer risk and competing life priorities. This fits well with Sackett’s41 notion that evidence-based medicine integrates the best research evidence with clinical expertise and patient values. To gain truly informed consent, all three elements need to be discussed and considered. Importantly, we found individuals who have agreed to undertake GS can experience continual decisional conflict about the type of results they would like returned, highlighting a need for health professionals to check in with individuals about their wider lives and needs before gaining consent and providing results.

Limitations and strengths

Interviewees were participants of a larger GS research study and may be positively biased towards genomics. Our sample consisted of individuals with a personal history of cancer, whose knowledge, motivation and decision making may differ without such history. While this qualitative study provides an in-depth understanding of these participants’ views, findings are not generalisable to all patients offered cancer GS. However, this is one of the first studies to obtain data from a cohort of individuals with a personal history of diverse cancers deciding to undergo, and undergoing, GS.

Overall, this research provides important information on the interplay between understanding of genomics, motivations and concerns when individuals are making the decision to undergo GS. Motivations, such as obtaining health information about self and family, were the main drivers for the participants in this study in deciding to undergo GS. However, some participants also expressed limited understanding and unrealistic expectations of the accuracy and utility of GS, which in some cases appeared to impact and prolong the deliberation process and contribute to ongoing decisional conflict. As the availability of GS increases and public interest in such testing continues to grow, understanding the multitude of interacting factors contributing to individuals’ decisions to pursue GS will allow health professionals to manage expectations and adequately support individuals in their decision making. To further facilitate development of empirically based strategies to help health professionals to address patient understanding and attitudes, future research efforts could be directed towards exploration of the balance between detailed knowledge versus ‘gist’ understanding of GS and the impact that this and factors such as trust in healthcare professionals have on motivations, concerns and the decision-making process.


Members of the Psychosocial Issues in Genomic Oncology (PiGeOn) Project are named authors, plus David Goldstein, Katherine Tucker, Timothy Schlub, Richard Vines, Kate Vines, Judy Kirk, Mary-Anne Young and Christine Napier.



  • Contributors Study concept and design: PB, MB, CJ, IJ, AJN, JS, BM, MLB, DMT and BB; acquisition, analysis and interpretation of data: NB, PB, MB, CJ, IJ, AJN, JS, BM and BB; drafting the manuscript: NB; critical revision of the manuscript: PB, MB, CJ, IJ, AJN, JS, BM, MLB, DMT and BB; accountable for all aspects of the work in ensuring that questions related to the accuracy or integrity of any part of the work are appropriately investigated and resolved: all authors; final approval of the submitted manuscript: all authors; obtained funding: PB; study supervision: PB and MB.

  • Funding The PiGeOn Project is funded by a National Health and Medical Research Council (NHMRC) of Australia Project Grant (ID1124749). Investigators received the following support: PB: NHMRC Senior Principal Research Fellowship (APP1121630); MB: Post-Doctoral Research Fellowship from the Cancer Institute of NSW (MB00352); BM: NHMRC Senior Research Fellowship Level B (ID1078523); MLB: Cancer Institute NSW Career Development Fellowship (CDF171109); DMT: NHMRC Principal Research Fellowship (APP1104364).

  • Disclaimer No funding body had any input in the design of the study, or collection, analysis and interpretation of data or in writing the manuscript.

  • Competing interests BM has a remunerated consultant role with the company Astrazeneca with respect to an unrelated project. The other authors declare no conflicts of interest.

  • Patient consent for publication Not required.

  • Ethics approval The St Vincent’s Hospital Human Research Ethics Committee reviewed and approved this study (HREC/16/SVH/24).

  • Provenance and peer review Not commissioned; externally peer reviewed.

  • Data availability statement Data are available on reasonable request. Deidentified data are available from the corresponding author NB, The Psycho-Oncology Cooperative Research Group, School of Psychology, Faculty of Science, The University of Sydney.