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81.
Caryn Lerman Janet Seay Andrew Balshem Janet Audrain 《American journal of medical genetics. Part A》1995,57(3):385-392
The recent cloning of a breast-ovarian cancer susceptibility gene (BRCA1), and determination of the locus of a related gene (BRCA2), offers potential for clinical genetic testing for breast cancer susceptibility. This study examined interest in and expectations about an impending genetic test among first-degree relatives (FDRs) of breast cancer patients. One hundred five females completed two structured telephone interviews to assess demographics, breast cancer risk factors, psychological factors, and attitudes about genetic testing for breast cancer susceptibility. Overall, 91% of FDRs said that they would want to be tested, 4% said they would not, and 5% were uncertain. The most commonly cited reasons for wanting genetic testing were to learn about one's children's risk, to increase use of cancer screening tests, and to take better care of oneself. Women with less formal education were motivated by childbearing decisions and future planning to a greater degree than were women with education beyond high school. Most women anticipated a negative psychological impact of positive test results, involving increased anxiety (83%), depression (80%), and impaired quality of life (46%). In addition, 72% of women indicated that they would still worry if they tested negative. In multivariate regression analysis, level of baseline depression was the strongest predictor of an anticipated negative impact of genetic testing (Beta =.15; P,.0001). These results suggest that the demand for genetic testing for breast cancer susceptibility may be great, even among women who are not likely to have predisposing mutations. Prior to widespread availability of such testing, it will be critical to develop informed consent protocols to educate individuals about the benefits and limitations of predictive testing for this multifactorial disease. © 1995 Wiley-Liss, Inc. 相似文献
82.
Helga V. Toriello James V. Higgins John M. Opitz 《American journal of medical genetics. Part A》1983,15(4):601-606
Data on the occurrence of neural tube defects in first-, second-, and third-degree relatives of probands were collected in a United States study. The proportions of affected individuals were 3.2%, 0.5%, and 0.17% respectively. These findings are compared to those from other recent North American studies, and differences are discussed. It is pointed out that accurate recurrence risk figures may not be available, and that caution should be used when counseling families with relatives who are affected with NTD. 相似文献
83.
84.
Joseph K. Kovach 《Behavior genetics》1993,23(4):369-377
Successful artificial selection of quail (C. coturnix japonica) for divergent early approach preferences for, and imprintabilities to, the wavelength characteristics of otherwise identical visual stimuli decreased the trait's developmental stability. The developmental error that resulted from selecting for extreme initial preferences was associated with enhanced imprintabilities. Conversely, the developmental error that resulted from selecting for extreme imprintabilities was associated with enhanced expression of directional gene effects in extreme initial preferences. The data are attributed to selectively relaxed normative canalization of trait development, and to related enhanced expression of genetic, environmental, and stochastic influences in trait deviations. 相似文献
85.
86.
Bartha Maria Knoppers 《American journal of medical genetics. Part A》2002,108(1):29-35
The word “serious” appears in laws and policies regarding genetics services but is not defined. Genetics professionals would most likely be consulted if definitions are made. We surveyed all U.S. board‐certified genetics services providers and all members of the European Society of Human Genetics (ESHG), Canadian College of Medical Geneticists (CCMG), and Ibero‐American Society of Human Genetics (IASHG), using anonymous, mailed questionnaires. Respondents were asked to list three conditions they considered lethal, three that were serious but not lethal, and three that were not serious. Of 3,317 asked to respond, 1,481 (45%) returned questionnaires. Analysis was limited to responses of the 1,264 (85%) who saw patients. Respondents listed 537 conditions, with extensive overlap between categories; 46% of conditions listed as serious were also listed as not serious and 41% were listed as lethal. Respondents did not want professional societies, laws, or national ethics committees to define serious. They favored individual patients as decision makers, with the help of individual doctors. Their reasons were that genetic disorders vary in expression, individuals perceive disorders differently, professional or legal definitions could be unfair to minority groups, definitions tend to be inflexible when new treatments appear. In the United States, most would not use a definition of serious to limit reproductive services, carrier screening, or neonatal intensive care; outside the United States, more supported limitations. There is not sufficient consensus among experienced genetics professionals to define serious genetic conditions for purposes of law or policy. Responses point to social and economic influences on perceptions of what constitutes a serious genetic disorder. © 2002 Wiley‐Liss, Inc. 相似文献
87.
Yamasaki M Takeshima Y Fujii S Kitaguchi S Matsuura M Tagawa K Inai K 《Pathology international》2000,50(10):778-785
Bronchiolo-alveolar carcinoma (BAC) is a type of lung adenocarcinoma characterized by growth along the alveolar wall. It is divided into two subtypes: sclerosing BAC (SBAC), which has central fibrosis, and non-sclerosing BAC (NSBAC), which lacks central fibrosis. We compared the genetic alterations in these two types of BAC with those in atypical adenomatous hyperplasia (AAH). There were 39 cases of SBAC, 19 of NSBAC and 20 of AAH. To detect the loss of heterozygosity (LOH) we used the microsatellite markers D3S1234 and D3S1300 on chromosome 3p, IFNA and D9S144 on 9p, and TP53 on 17p. We also used polymerase chain reaction-SSCP analysis and direct sequencing to examine a point mutation of the p53 gene at exons 5-8. At the TP53 locus, the frequencies of LOH showed a statistical rank-difference correlation among AAH, NSBAC and SBAC. On chromosomes 3p and 9p there were no statistical differences of LOH among AAH, NSBAC and SBAC. We detected a significant statistical rank-difference correlation in the p53 mutation among AAH, NSBAC and SBAC. These findings suggest that a process of multistep carcinogenesis from AAH through NSBAC to SBAC might occur in some cases of adenocarcinoma, and LOH of 3p and 9p might be an early event of carcinogenesis, while the p53 mutation might be a later event. 相似文献
88.
Studies from the last decade on factors influencing reproductive planning after genetic counselling were reviewed. Increased possibilities of DNA-analysis and prenatal diagnosis might have brought about a shift in the paramountcy of factors influencing reproductive planning after genetic counselling. In contrast to the literature in the seventies, the magnitude of the genetic risk was no longer found to be one of the decisive factors in postcounselling reproductive planning. Instead, the interpretation of the risk as high or low and the desire to have children appeared to be paramount. The impact of new developments in DNA-analysis in prenatal diagnosis and presymptomatic testing will be an important subject for future studies on factors influencing reproductive planning. 相似文献
89.
Evaluation of genetic counselling: recall of information, post-counselling reproduction, and attitude of the counsellees 总被引:2,自引:0,他引:2
Of the families who had received genetic counselling between 1972 and 1981, 791 replied to a questionnaire which covered recall of information, post-counselling reproduction and attitudes towards counselling and prenatal diagnosis. Eighty percent had adequate knowledge of mode of inheritance and 74% of recurrence risk. Knowledge of mode of inheritance was poorest in multifactorial transmission (63%) and knowledge of recurrence risk in X-chromosomal disorders (61%). Forty-five per cent of the families had started a pregnancy after the counselling. 25%). Early lethality of the disorder and feasibility of a prenatal study contributed to positive reproductive decisions. Nine per cent of the children born after the counselling were affected by the disorder in question. The observed risks tended to match well with the expected ones. Sixty-two per cent of the respondents felt that the counselling had had a great or moderate impact on their reproductive plans. Forty-two per cent expressed a wish to hear the counsellor's opinion in addition to the facts. This was more common when the disorder was severe. Although most couples (53%) wished to have a prenatal study, if feasible, and abort an affected foetus, 16% were against abortion in such a case and 31% wished to have the study but were ambiguous about an abortion. 相似文献
90.
Patient and parental attitudes toward genetic screening and its implications at an adult cystic fibrosis centre 总被引:2,自引:0,他引:2
General population screening for cystic fibrosis carrier status in the United Kingdom would detect 72% of at-risk couples. Proper counselling would allow these couples to make informed reproductive choices, including the possibility of prenatal diagnosis and the termination of an affected pregnancy. However, children with cystic fibrosis born in this decade, given optimum treatment, now have an average life expectancy of 40 years, and there is no unanimity of opinion on how, where, when, or even if, screening should be offered. The purpose of this questionnaire-based study was to examine the attitudes of an adult clinic population who have grown up with cystic fibrosis, and of their parents, towards genetic screening programmes and the controversies and ethical dilemmas surrounding such programmes in cystic fibrosis. Both patients and parents supported prenatal screening (88% and 90%) and the option of terminating an affected pregnancy (68% and 84%). Only 22% of patients and 10% of parents felt that screening should be limited to families with a history of cystic fibrosis, and 19% and 6%, respectively, that prenatal diagnosis should be restricted to those with a previous child with cystic fibrosis. Despite the negative aspects of any screening programme and the acknowledged ethical problems peculiar to cystic fibrosis, the conclusion of our patients and parents who have lived intimately with the illness is that there should be the option of utilising information available from genetic screening for cystic fibrosis to guide reproductive choices. Pilot programmes to define the optimum management of such screening should continue. 相似文献