PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Genetic testing”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 739 records · Page 41Linked to original sources

Postmortem long QT syndrome genetic testing for sudden unexplained death in the young.

OBJECTIVES: This study sought to determine the spectrum and prevalence of long QT syndrome (LQTS)-associated mutations in a large cohort of autopsy-negative sudden unexplained death (SUD). BACKGROUND: Potentially heritable arrhythmia syndromes may explain a significant proportion of SUD in the young. Here, comprehensive postmortem LQTS genetic testing was performed in a cohort of SUD cases. METHODS: From September 1998 to March 2004, 49 cases of SUD (30 male patients, average age at death 14.2 +/- 10.9 years) were referred by medical examiners/coroners to Mayo Clinic's Sudden Death Genomics Laboratory. Using polymerase chain reaction, denaturing high-performance liquid chromatography, and direct DNA sequencing, open reading frame/splice site mutational analysis was conducted for all 8 genes implicated in the pathogenesis of either LQTS (LQT1 to LQT6) or multisystem disorders involving either QT or QU prolongation. RESULTS: Ten LQTS-associated mutations (4 novel) were discovered in 10 SUD cases (20%, 8 female patients, average age at death 18.0 +/- 11.8 years). The LQTS susceptibility mutations LQT1 (5), LQT2 (3), and LQT3 (2) were far more common among women (8 of 18, 44%) than men (2 of 30, 6.7%, p < 0.008). The activities at the time of SUD included sleep (5), exertion (2), auditory arousal (1), and undetermined (2). Sudden death was the sentinel event in two-thirds of the cases. CONCLUSIONS: In this cardiac channel-focused molecular autopsy investigation of SUD, over one-third of decedents harbored a putative cardiac channel mutation: 7 previously reported to host mutations in the RyR2-encoded calcium release channel and now 10 with LQTS susceptibility mutations. Accordingly, postmortem cardiac channel genetic testing should be pursued in the evaluation of autopsy-negative SUD.

Adolescent↗

[Genetic tests for molecular markers of cancer].

Based on recent advancements in biotechnology and molecular oncology, genetic tests for molecular markers have been widely used for diagnosis and therapeutic monitoring in patients with hematological malignancies. However, incorporation of such tests has been limited in the care of patients with non-hematopoietic malignancies. The reasons for this include difficulty in sampling of the tumor tissue, and a lack of evidence for cost-effectiveness in the test utilization. A practical approach is the use of bodily fluids, such as blood, sputum, urine and feces, as specimens for early detection and monitoring of tumor-derived nucleic acid sequences. The prospect has been raised for development of tests for individualized medicine based on genetic information such as prediction of responsiveness to chemotherapeutic agents for selection of treatment, which will be promoted by gene expression profiling using DNA microarray.

Biomarkers, Tumor↗

The role of genetic testing and effect on patient care.

The heralded report of the first draft of the Human Genome Project highlights the role genetics plays in nearly all medical disciplines, including dermatology. Many inherited disorders have dermatological features, and dermatological pathologic conditions frequently can be traced to a genetic cause. Suspicion of a genetic disorder is often suggested first by a practitioner such as a dermatologist, who is likely to be the first to identify characteristic features of the disease. This review highlights the relationship between the clinician and genetics professional in genetic testing using a case example of a familial cancer syndrome, Cowden syndrome, as a model.

Female↗

Genetic testing for risk stratification in hypertrophic cardiomyopathy and long QT syndrome: fact or fiction?

PURPOSE OF REVIEW: Hypertrophic cardiomyopathy, affecting 1 in 500 persons, is the most common identifiable cause of sudden cardiac death in the young, whereas congenital long QT syndrome, affecting 1 in 5000 persons, is perhaps one of the most common causes of autopsy negative sudden unexplained death. Since May 2004, genetic testing has been available as a clinical diagnostic test for both hypertrophic cardiomyopathy and long QT syndrome. It is now critical to carefully scrutinize the relationships between genotype and phenotype as they pertain to clinical practice. RECENT FINDINGS: In 1990, the molecular underpinnings of hypertrophic cardiomyopathy were exposed with the identification of a mutation in the MYH7-encoded beta myosin heavy chain. Since then, hundreds of mutations scattered among at least 14 genes confer the pathogenetic substrate for this 'disease of the sarcomere'. In 1995, the discipline of cardiac channelopathies was born with the revelation that mutations in critical cardiac channel genes cause long QT syndrome. Today, hundreds of mutations involving several cardiac channel genes account for approximately 75% of long QT syndrome. Over the past decade, scores of genotype-phenotype correlation studies in both hypertrophic cardiomyopathy and long QT syndrome have been conducted. SUMMARY: Genomic medicine has now entered the clinical practice as it pertains to the evaluation and management of both hypertrophic cardiomyopathy and long QT syndrome. The diagnostic utility of genetic testing for both diseases is clearly evident, as well as current limitations. While treatment decisions are certainly influenced by knowing the underlying genotype in long QT syndrome, there seems to be negligible prognostic value associated with particular hypertrophic cardiomyopathy-causing mutations at this time.

Cardiomyopathy, Hypertrophic↗

Genetic testing for pheochromocytoma-associated syndromes.

Pheochromocytoma and paraganglioma are tumors of the autonomic nervous system. Various syndromes have been found to be associated with the development of pheochromocytomas and paragangliomas: multiple endocrine neoplasia type 2 (MEN 2, susceptibility gene: RET), von Hippel-Lindau disease (VHL, susceptibility gene: VHL), neurofibromatosis 1 (NF 1), and paraganglioma syndromes type 1, 3, and 4 (susceptibility genes: succinate dehydrogenase gene, SDH, subunits D, C and B, respectively). Prevalence and clinical features of pheochromocytomas and paragangliomas are different for each of these syndromes. Mutational analysis of the susceptibility genes of these syndromes in patients presenting with pheochromocytoma or paraganglioma may help to judge the risks of multifocality of the tumor as well as development of malignant pheochromocytoma or of other malignant tumors. Here we review the recent progress in clinical characterization and genetic testing for these syndromes. Based on tumor characteristics and prevalence data we give recommendations for an efficient genetic testing procedure in patients presenting with pheochromocytomas and paragangliomas.

Adrenal Gland Neoplasms↗

[Genetic testing in pregnancy].

First trimester risk screening is probably the major methodological advance in identifying pregnancies at increased risk for genetic disease during recent years with an impact on all pregnancies. The high detection rate with moderate false positive rates will reduce the over-all number of invasive procedures as compared to the traditional approach based on maternal age exclusively, in particular considering the demographic shift towards higher mean maternal age. Non-invasive prenatal diagnosis from fetal cells or DNA in the maternal circulation remains an experimental approach, despite a growing number of reports on successful diagnoses of single gene disorders. In the lab molecular cytogenetic approaches have considerably broadened the diagnostic spectrum of conventional karyotyping and facilitated a rapid diagnosis of selected frequent aneuploidies. Molecular genetic testing, in particular on chorionic villi, allows an early and reliable diagnosis of a growing number of severe monogenic conditions. A restrictive legislation has hampered the development of preimplantation genetic diagnosis in German speaking countries, only a few groups work on polar body diagnosis, a legal but restricted alternative.

Adult↗

Attitudes of genetic counselors towards expanding newborn screening and offering predictive genetic testing to children.

There is movement to expand newborn screening (NBS) to include conditions that challenge the traditional public health screening criteria. Little is known about the attitudes of genetic counselors towards expanding NBS and offering predictive genetic tests to children. For our study genetic counselors completed an internet survey posted on the National Society of Genetic Counselors Listserv regarding five conditions: cystic fibrosis (CF), Duchenne muscular dystrophy (DMD), glucose-6-phosphate dehydrogenase deficiency (G6PD), fragile X (FraX), and type 1 diabetes (T1D). The survey addressed attitudes towards: (1) testing high-risk infants; (2) mandatory NBS; (3) population screening beyond the newborn period; and (4) testing one's own child. Two hundred sixty-seven usable surveys were received. Over two-thirds of respondents supported testing high-risk infants for all conditions except T1D (22%). CF was the only condition for which there was majority support for both mandatory NBS (56%) and later population screening (60%). For all other conditions, later population screening was preferred over NBS (P <or= 0.01). Genetic counselors were most likely to test their own child for CF (46%) and least likely to test their own child for T1D (6%). For each condition, genetic counselors were more likely to support NBS if they chose to screen their own newborn (P < 0.001). Attitudes towards NBS were not influenced by year of graduation or professional experience. We can conclude that genetic counselors are supportive of targeted testing of high-risk infants. They prefer voluntary population screening with consent to mandatory NBS for conditions that challenge Wilson and Jungner criteria. Their support for NBS correlates with their interest in testing their own children and not with professional experience.

Attitude of Health Personnel↗

Identifying mutations in autoinflammatory diseases: towards novel genetic tests and therapies?

Autoinflammatory diseases are defined as illnesses caused by primary dysfunction of the innate immune system. This new concept includes a broad number of disorders, but the spotlight has been focused for the past two years on periodic fevers (familial Mediterranean fever [FMF]; mevalonate kinase deficiency [MVK]; tumor necrosis factor [TNF] receptor-associated periodic syndrome [TRAPS]; cryopyrin-associated periodic syndrome [CAPS]), Crohn's disease and Blau syndrome, thanks to the recent understanding of their molecular basis. Indeed, until recently, these conditions were defined only by phenotypical features, the main ones being recurrent attacks of fever, abdominal pain, arthritis, and cutaneous signs, which sometimes overlap, obscuring diagnosis. The search for distinguishing signs such as periorbital edema in TRAPS, and the use of specific functional tests where available, are valuable. Needless to say, molecular screening of the causative genes has dramatically improved patient quality-of-life by providing early and accurate diagnosis, subsequently allowing for the appropriate treatment. Some patients, however, remain hard to manage despite the advent of new genetic tests, and/or due to the lack of effective treatment. The original clinical link between the aforementioned diseases can now be confirmed by a molecular one, following the exciting discovery that most of the altered proteins are related to the death domain fold (DDF) superfamily involved in inflammation and apoptosis. These molecules mediate the regulation of nuclear factor-kappa B (NF-kappa B) activation, cell apoptosis, and interleukin-1 beta secretion through cross-regulated and, sometimes, common signaling pathways. Knowledge of the defective step in autoinflammation has already led to the elucidation of the mechanisms of action of existing drugs and may allow the development of new therapies.

Genetic Testing↗

Confronting the "gray zones" of technology assessment: evaluating genetic testing services for public insurance coverage in Canada.

We describe an evaluation model to guide public coverage of new predictive genetic tests in Ontario, Canada. The model confronts common "gray zones" in evaluation and coverage policy for challenging new technologies. Analysis addresses three domains of the evaluation picture. The first specifies evaluative criteria (purpose, effectiveness, additional effects, unit cost, demand, cost-effectiveness). The second induces or deduces acceptable cutoffs for each criterion. The third domain addresses the need to make decisions under uncertainty and to respond to "gray" evaluations with conditional-coverage decisions. The evaluation criteria should be applied within sound decision-making processes.

Canada↗

Impact of genetic testing for Huntington disease on the family system.

The psychological impact of DNA predictive testing on asymptomatic individuals at risk for Huntington disease (HD) has received considerable attention since the advent of the procedure in 1993. This study examined the impact of such testing on families from the families' perspective. Individuals asymptomatic at the time of testing, together with their families, were interviewed in their homes with a semi-structured interview. Eighteen families with a total of 55 individuals participated. Defining the family as the unit of analysis was consistent with Systems Theory that links interactions of individuals, families, and the social environment. Areas of affected family functioning noted by the respondents included: 1) family membership; 2) family patterns of communication; and 3) future care giving concerns as they influenced current relationships. Eighty-one percent of families experienced changes in family membership. Members in 50% of families experienced changes in patterns of communication, and 56% percent of persons reported changes in current relationships in response to test results and their implications for future caregiving. The data support the conclusion that genetic testing is a family, as opposed to an individual, matter and that family involvement in the decision making process should be strongly encouraged in order to help families adjust. The data imply that families will benefit in pre-test sessions from an examination of their patterns of dealing with illness issues, both past and present.

Adult↗

[Genetic testing in occupational environmental context].

Individuals with an increased risk of occupationally and nonoccupationally induced adverse health effects may be identified by genetic monitoring and genetic screening. Genetic monitoring of induced genetic changes is performed by measurements of chromosomal aberrations or DNA-lesions. Genetic screening includes detection of inherited traits by measurements of enzyme activities in blood, the presence of a specific gene or a specific mutation. Inherited serum alpha-1-antitrypsin deficiency increases the risk of developing a chronic obstructive pulmonary disease. The risk is exacerbated by occupational exposure to dust. The available methods used for genetic screening of individual susceptibility to occupational exposures are not sufficiently validated for routine use. This is especially relevant concerning the population validity referring to how well the markers depict an event in a population. Legal and ethical aspects of preemployment genetic testing are currently discussed in Denmark.

Evaluation Studies as Topic↗

The "genetic test request": A genomic stewardship intervention for inpatient exome and genome orders at a tertiary pediatric hospital.

PURPOSE: Exome sequencing (ES) and genome sequencing (GS) are useful tests to diagnose rare diseases in pediatric patients in critical care settings. Genomic test stewardship can increase the appropriate use of these tests leading to improved diagnostics and cost savings. METHODS: A mandatory review of ES and GS orders for admitted patients was implemented in March 2023. Outcomes of the reviews, cost analysis, and subsequent test results through February 2024 were analyzed with descriptive statistics. RESULTS: There were 444 genetic test request orders placed for 412 unique patients. Of these, 81 (18.2%) were redirected and 57 (12.8%) required modification after approval, leading to an overall cost savings of $345,821.00 or $778.88 per order. The combined diagnostic rate was 28.2% in this patient population. CONCLUSION: Stewardship of ES/GS orders for pediatric inpatients is an effective tool to improve the appropriate usage of these genomic tests. Additional collaboration with stakeholders and expansion of genomic stewardship initiatives may shorten the diagnostic odyssey for critically ill pediatric patients and result in cost savings.

Humans↗

Parents' responses to disclosure of genetic test results of their children.

The psychological reactions of 22 parental couples and 3 single parents were investigated after disclosure of genetic test results of their children. The children were tested for the early-onset, monogenetic cancer disorder multiple endocrine neoplasia type 2. Participants came from 13 different families and were aged between 28 and 47 years. Parents who were informed that their child was a gene carrier reacted with resignation, showed moderate to high levels of test-related and general anxiety, but few psychological complaints. Daily activities were disturbed in 43% of the parents with carrier-children. There was little disruption of the parents' future perspective, apart from some socioeconomic disadvantages and increased parental concern for the carrier-children. Most parents with carrier-children showed restraint with respect to short-term prophylactic treatment. Parents with favorable test results showed significantly less anxiety and no disturbance in their daily activities. They did not, however, seem to be reassured by the DNA test result. These parents questioned the reliability of the DNA test, wanted confirmation of the test results, and were eager to continue screening of their noncarrier children. Parents, especially those with a lower level of education and/or a pessimistic view of the future, were distressed by unfavorable test results. Additional counseling is advised to prevent parents of carrier-children worrying unnecessarily, or parents with children in whom the disease gene was not found being not reassured. Am. J. Med. Genet. 94:316-323, 2000.

Adolescent↗

Echocardiography-guided genetic testing in hypertrophic cardiomyopathy: septal morphological features predict the presence of myofilament mutations.

OBJECTIVE: To examine the relationship among age, septal morphological subtype, and presence of hypertrophic cardiomyopathy (HCM)-associated myofilament mutations. PATIENTS AND METHODS: Comprehensive mutation analysis of the 8 HCM susceptibility genes that encode the myofilaments of the cardiac sarcomere was performed previously in 382 unrelated patients with HCM. Blinded to genotype status, we used echocardiography to characterize the left ventricular morphological features. Multivariate regression was used to assess the relationship among morphological subtypes, clinical data, and genetic variables. RESULTS: The mean +/- SD age of the patients was 41.6+/-19.0 years, with 126 patients 50 years or older at initial diagnosis. The septal morphological subtype was sigmold in 181 (47%), reverse in 132 (35%), apical variant in 37 (10%), and neutral in 32 (8%). The HCM-associated myofilament mutations were Identified in 143 patients (37%). Multivariate analysis showed that the reverse curvature septal morphological subtype was a strong predictor of genotype-positive status (odds ratio, 21; P<.001). Overall, the yield of HCM genetic testing was 79% in the setting of reverse curvature HCM but only 8% in sigmold septal HCM. CONCLUSION: In stark contrast to HCM in young patients, elderly patients with HCM display a predominantly sigmoid septal morphological subtype and uncommonly have perturbations of known HCM susceptibility genes. Independent of age, septal morphological subtype strongly predicts the presence or absence of HCM-associated myofilament mutations and may enable echocardiography-guided genetic testing for HCM.

Actin Cytoskeleton↗

Factor V Leiden and allogeneic bone marrow transplantation: chimerism as a confounding factor in genetic test interpretation.

Factor V Leiden is one of the most common genetic conditions predisposing to venous thrombosis. Diagnosis is currently made by plasma activity assay for activated protein C (APC) resistance or polymerase chain reaction (PCR)-based DNA assay. The occurrence of factor V Leiden is reported in a patient affected by acute myeloid leukaemia submitted to allogeneic bone marrow transplantation from an HLA identical sister. The donor was not affected by the factor V mutation. The patient did not develop thrombosis during induction and consolidation chemotherapy and the post-transplantation course was not complicated by thrombosis or veno-occlusive disease. At engraftment, PCR analysis showed the disappearance of factor V Leiden. Genetic tests on DNA after allogeneic marrow transplantation should be carefully interpreted as a result of donor chimerism.

Bone Marrow Transplantation↗