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Dive into the research topics where Clara Gaff is active.

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Featured researches published by Clara Gaff.


European Journal of Human Genetics | 2007

Process and outcome in communication of genetic information within families: a systematic review

Clara Gaff; Angus John Clarke; Paul Atkinson; Stephanie Sivell; Glyn Elwyn; Rachel Iredale; Hazel Thornton; Joanna Dundon; Christine Shaw; Adrian Edwards

The communication of risk is a central activity in clinical genetics, with genetic health professionals encouraging the dissemination of relevant information by individuals to their at-risk family members. To understand the process by which communication occurs as well as its outcomes, a systematic review of actual communication in families about genetic risk was conducted. Findings from 29 papers meeting the inclusion criteria were summarised and are presented narratively. Family communication about genetic risk is described as a deliberative process, in which: sense is made of personal risk; the vulnerability and receptivity of the family member is assessed; decisions are made about what will be conveyed; and the right time to disclose is selected. The communication strategy adopted will depend on these factors and varies within families as well as between families. Inherent in these processes are conflicting senses of responsibility: to provide potentially valuable information and to prevent harm that may arise from this knowledge. However, the research ‘outcomes’ of communication have been professionally determined (number of relatives reported as informed, uptake of testing, knowledge of the recipient) and are typically unrelated to the concerns of the family member. The impact of communication on the individual, family members, and family relationships is of concern to the individual conveying the information, but this is largely self-reported. Currently, there is insufficient information to inform the development of theoretically and empirically based practice to foster ‘good’ communication. The implications for future research are discussed.


American Journal of Human Genetics | 2002

The Founder Mutation MSH2*1906G→C Is an Important Cause of Hereditary Nonpolyposis Colorectal Cancer in the Ashkenazi Jewish Population

William D. Foulkes; Isabelle Thiffault; Stephen B. Gruber; Marshall S. Horwitz; Nancy Hamel; C. Lee; J. Shia; Arnold J. Markowitz; A. Figer; Eitan Friedman; D. Farber; Celia M. T. Greenwood; Joseph D. Bonner; Khedoudja Nafa; T. Walsh; Victoria Marcus; Lynn P. Tomsho; J. Gebert; Finlay Macrae; Clara Gaff; B. Bressac-de Paillerets; Peter K. Gregersen; Jeffrey N. Weitzel; Philip H. Gordon; Elizabeth MacNamara; Mary Claire King; Heather Hampel; A. de la Chapelle; Jeff Boyd; K. Offit

Hereditary nonpolyposis colorectal cancer (HNPCC) is caused by mutations in the mismatch-repair genes. We report here the identification and characterization of a founder mutation in MSH2 in the Ashkenazi Jewish population. We identified a nucleotide substitution, MSH2*1906G-->C, which results in a substitution of proline for alanine at codon 636 in the MSH2 protein. This allele was identified in 15 unrelated Ashkenazi Jewish families with HNPCC, most of which meet the Amsterdam criteria. Genotype analysis of 18 polymorphic loci within and flanking MSH2 suggested a single origin for the mutation. All colorectal cancers tested showed microsatellite instability and absence of MSH2 protein, by immunohistochemical analysis. In an analysis of a population-based incident series of 686 Ashkenazi Jews from Israel who have colorectal cancer, we identified 3 (0.44%) mutation carriers. Persons with a family history of colorectal or endometrial cancer were more likely to carry the mutation than were those without such a family history (P=.042), and those with colorectal cancer who carried the mutation were, on average, younger than affected individuals who did not carry it (P=.033). The mutation was not detected in either 566 unaffected Ashkenazi Jews from Israel or 1,022 control individuals from New York. In hospital-based series, the 1906C allele was identified in 5/463 Ashkenazi Jews with colorectal cancer, in 2/197 with endometrial cancer, and in 0/83 with ovarian cancer. When families identified by family history and in case series are included, 25 apparently unrelated Ashkenazi Jewish families have been found to harbor this mutation. Although this pathogenic mutation is not frequent in the Ashkenazi Jewish population (accounting for 2%-3% of colorectal cancer in those whose age at diagnosis is <60 years), it is highly penetrant and accounts for approximately one-third of HNPCC in Ashkenazi Jewish families that fulfill the Amsterdam criteria.


British Journal of Cancer | 2004

Communication and information-giving in high-risk breast cancer consultations: influence on patient outcomes.

Elizabeth Lobb; Phyllis Butow; Alexandra Barratt; Bettina Meiser; Clara Gaff; Mary-Anne Young; Eric Haan; Graeme Suthers; Michael Gattas; Katherine L. Tucker

This longitudinal study aimed to document (i) the information-giving and patient-communication styles of clinical geneticists and genetic counsellors (consultants) in familial breast cancer clinics and (ii) assess the effect of these styles on womens knowledge, whether their expectations were met, satisfaction, risk perception and psychological status. A total of 158 women from high-risk breast cancer families completed self-report questionnaires at 2 weeks preconsultation and 4 weeks postconsultation. The consultations were audiotaped, transcribed and coded. Multivariate logistic regressions showed that discussing prophylactic mastectomy (P=0.00) and oophorectomy (P=0.01) led to women having significantly more expectations met; discussing genetic testing significantly decreased anxiety (P=0.03) and facilitating understanding significantly decreased depression (P=0.05). Receiving a summary letter of the consultation significantly lowered anxiety (P=0.01) and significantly increased the accuracy of perceived risk (P=0.02). Women whose consultant used more supportive communications experienced significantly more anxiety about breast cancer at the 4 weeks follow-up (P=0.00). These women were not significantly more anxious before genetic counselling. In conclusion, this study found that consultants vary in the amount of information they give and the way they communicate; and this variation can result in better or worse psychosocial outcomes. Greater use of supportive and counselling communications appeared to increase anxiety about breast cancer. Identifying methods to assist consultants to address emotional issues effectively may be helpful.


Journal of Genetic Counseling | 2005

Facilitating family communication about predictive genetic testing: probands' perceptions.

Clara Gaff; Veronica Collins; Tiffany Symes; Jane Halliday

The responsibility of informing relatives that predictive genetic testing is available often falls to the proband. Support is required during this process, however the perceived utility of genetic counseling and other strategies to facilitate communication have not been explored. We investigated the experiences of 12 individuals with hereditary nonpolyposis colorectal cancer (HNPCC) in a semistructured telephone interview. Respondents informed their immediate family about the availability of genetic testing, however many more-distant relatives were not directly informed. Respondents were mostly satisfied with the way they told family members about testing and had mixed views about the usefulness of genetic counseling. Gender differences were observed, with most men expressing a need for guidance or support in communicating to relatives. Letters and booklets were thought to enhance the quality of information but the provision of further aids is unlikely to increase the number of relatives made aware of predictive testing by the proband.


Genetics in Medicine | 2016

A prospective evaluation of whole-exome sequencing as a first-tier molecular test in infants with suspected monogenic disorders.

Zornitza Stark; Tiong Yang Tan; Belinda Chong; Gemma R. Brett; Patrick Yap; Maie Walsh; Alison Yeung; Heidi Peters; Dylan Mordaunt; Shannon Cowie; David J. Amor; Ravi Savarirayan; George McGillivray; Lilian Downie; Paul G. Ekert; Christiane Theda; Paul A. James; Joy Yaplito-Lee; Monique M. Ryan; Richard J. Leventer; Emma Creed; Ivan Macciocca; Katrina M. Bell; Alicia Oshlack; Simon Sadedin; Peter Georgeson; Charlotte Anderson; Natalie P. Thorne; Clara Gaff; Susan M. White

Purpose:To prospectively evaluate the diagnostic and clinical utility of singleton whole-exome sequencing (WES) as a first-tier test in infants with suspected monogenic disease.Methods:Singleton WES was performed as a first-tier sequencing test in infants recruited from a single pediatric tertiary center. This occurred in parallel with standard investigations, including single- or multigene panel sequencing when clinically indicated. The diagnosis rate, clinical utility, and impact on management of singleton WES were evaluated.Results:Of 80 enrolled infants, 46 received a molecular genetic diagnosis through singleton WES (57.5%) compared with 11 (13.75%) who underwent standard investigations in the same patient group. Clinical management changed following exome diagnosis in 15 of 46 diagnosed participants (32.6%). Twelve relatives received a genetic diagnosis following cascade testing, and 28 couples were identified as being at high risk of recurrence in future pregnancies.Conclusions:This prospective study provides strong evidence for increased diagnostic and clinical utility of singleton WES as a first-tier sequencing test for infants with a suspected monogenic disorder. Singleton WES outperformed standard care in terms of diagnosis rate and the benefits of a diagnosis, namely, impact on management of the child and clarification of reproductive risks for the extended family in a timely manner.Genet Med 18 11, 1090–1096.


Clinical Genetics | 2004

Psychological impact of genetic testing for hereditary non-polyposis colorectal cancer

Bettina Meiser; Veronica Collins; R Warren; Clara Gaff; Djb St John; M-A Young; K. Harrop; Judith E. Brown; Jane Halliday

The psychological impact of predictive genetic testing for hereditary non‐polyposis colorectal cancer (HNPCC) was assessed in 114 individuals (32 carriers and 82 non‐carriers) attending familial cancer clinics, using mailed self‐administered questionnaires prior to, 2 weeks, 4 months and 12 months after carrier status disclosure. Compared to baseline, carriers showed a significant increase in mean scores for intrusive and avoidant thoughts about colorectal cancer 2 weeks (t = 2.49; p = 0.014) and a significant decrease in mean depression scores 2 weeks post‐notification of result (t = −3.98; p < 0.001) and 4 months post‐notification of result (t = −3.22; p = 0.002). For non‐carriers, significant decreases in mean scores for intrusive and avoidant thoughts about colorectal cancer were observed at all follow‐up assessment time points relative to baseline. Non‐carriers also showed significant decreases from baseline in mean depression scores 2 weeks, 4 months and 12 months post‐notification. Significant decreases from baseline for mean state anxiety scores were also observed for non‐carriers 2 weeks post‐notification (t = −3.99; p < 0.001). These data indicate that predictive genetic testing for HNPCC leads to psychological benefits amongst non‐carriers, and no adverse psychological outcomes were observed amongst carriers.


European Journal of Human Genetics | 2010

Carrier screening for Beta-thalassaemia: a review of international practice

Nicole Cousens; Clara Gaff; Sylvia A. Metcalfe; Martin B. Delatycki

β-thalassaemia is one of the most common single-gene inherited conditions in the world, and thalassaemia carrier screening is the most widely performed genetic screening test, occurring in many different countries. β-thalassaemia carrier screening programmes provide a unique opportunity to compare the delivery of carrier screening programmes carried out in different cultural, religious and social contexts. This review compares the key characteristics of β-thalassaemia carrier screening programmes implemented in countries across the world so that the differences and similarities between the programmes can be assessed. The manner in which thalassaemia carrier screening programmes are structured among different populations varies greatly in several aspects, including whether the programmes are mandatory or voluntary, the education and counselling provided and whether screening is offered pre-pregnancy or antenatally. National and international guidelines make recommendations on the most appropriate ways in which genetic carrier screening programmes should be conducted; however, these recommendations are not followed in many programmes. We discuss the implications for the ethical and acceptable implementation of population carrier screening and identify a paucity of research into the outcomes of thalassaemia screening programmes, despite the fact that thalassaemia screening is so commonly conducted.


Patient Education and Counseling | 2001

Long-term outcomes of genetic counseling in women at increased risk of developing hereditary breast cancer

Bettina Meiser; Phyllis Butow; Alex Barratt; Vivienne Schnieden; Michael Gattas; Judy Kirk; Clara Gaff; Graeme Suthers; Katherine L. Tucker

This multicenter study evaluated the impact of genetic counseling in 218 women at risk of developing hereditary breast cancer. Women were assessed prior to counseling and 12-month post-counseling using self-administered, mailed questionnaires. Compared to baseline, breast cancer genetics knowledge was increased significantly at follow-up, and greater increases in knowledge were associated with educational level. Breast cancer anxiety decreased significantly from baseline to follow-up, and these decreases were associated with improvements in perceived risk. A significant decrease in clinical breast examination was observed at the 12-month follow-up. Findings suggest that women with a family history of breast cancer benefit from attending familial cancer clinics as it leads to increases in breast cancer genetics knowledge and decreases in breast cancer anxiety. The lowered rates of clinical breast examination indicate that the content of genetic counseling may need to be reviewed to ensure that women receive and take away the right message.


Genetics in Medicine | 2007

The impact of predictive genetic testing for hereditary nonpolyposis colorectal cancer: three years after testing

Veronica Collins; Bettina Meiser; Obioha C. Ukoumunne; Clara Gaff; D James St. John; Jane Halliday

Background: To fully assess predictive genetic testing programs, it is important to assess outcomes over periods of time longer than the 1-year follow-up reported in the literature.Methods: We conducted a 3-year study of individuals who received predictive genetic test results for previously identified familial mutations in Australian Familial Cancer Clinics. Questionnaires were sent before attendance at the familial cancer clinic and 2 weeks, 4 months, 1 year, and 3 years after receiving test results. Psychological measures were included each time, and preventive behaviors were assessed at baseline and 1 and 3 years. Psychological measures were adjusted for age, gender, and baseline score.Results: The study included 19 carriers and 54 non-carriers. We previously reported an increase in mean cancer-specific distress in carriers at 2 weeks with a return to baseline levels by 12 months. This level was maintained until 3 years. Non-carriers showed sustained decreases after testing with a significantly lower level at 3 years compared with baseline (P < 0.001). These scores tended to be lower than those for carriers at 3 years (P = 0.09). Mean depression and anxiety scores did not differ between carriers and non-carriers and, at 3 years, were similar to baseline. All carriers and 7% of non-carriers had had a colonoscopy by 3 years, and 69% of 13 female carriers had undergone gynecological screening in the previous 2 years. Prophylactic surgery was rare.Conclusion: This report of long-term data indicates appropriate screening and improved psychological measures for non-carriers with no evidence of undue psychological distress in carriers of hereditary nonpolyposis colorectal cancer mutations.


Cancer | 2005

Screening and preventive behaviors one year after predictive genetic testing for hereditary nonpolyposis colorectal carcinoma

Veronica Collins; Bettina Meiser; Clara Gaff; D. James B. St. John; Jane Halliday

Prevention benefits from predictive genetic testing for cancer will only be fully realized if appropriate screening is adopted after testing. The current study assessed screening and preventive behaviors during 12 months after predictive genetic testing for hereditary nonpolyposis colorectal carcinoma (HNPCC) in an Australian clinical cohort.

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Bettina Meiser

University of New South Wales

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Elizabeth Lobb

University of Notre Dame

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Zornitza Stark

Royal Children's Hospital

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Katherine L. Tucker

University of Massachusetts Lowell

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