View clinical trials related to Genetics.
Filter by:This is a family based genotype-phenotype study designed to assess genetic and environmental influences on obesity, insulin resistance and beta cell function in the context of gestational diabetes.
Obesity is the 5th leading cause of global death, and is major risk factors for many chronic diseases, such as type 2 diabetes, cardiovascular diseases, hypertension and cancer. Obesity is caused by an imbalance between energy intake and energy expenditure, and it is widely agreed to be a consequence of a gene by environment interaction. Although on average obesity rates are increasing, the shape of the distribution of adiposity is changing: it is becoming more right skewed. This is because there is a population of very lean subjects that has remained almost unchanged by the epidemic. The investigators have called these very lean individuals that are resistant to the epidemic and sustain a BMI < 18.5 kg/m2 'super lean' subjects. We have very little understanding of the lifestyles of these individuals and how they are able to maintain their super lean phenotype, and whether the basis of their leanness is primarily genetics.
This project focuses on myomectomy patients in reproductive age. The aim is to study both the molecular characteristics of uterine fibroids and to characterize the clinical effects of surgical treatment. Patient series is mainly retrospective and consists of individuals who have undergone myomectomy at Helsinki University Central Hospital (HUCH) during 2009-2015. In addition, the investigators have started a prospective sample collection starting in October 2015, collecting samples from myomectomies. Clinical data sources include medical records, specific questionnaires and a quality of life -questionnaire filled by patients.
Data on transgenerational effects following nuclear accidents are important for understanding fully the consequences of parental exposure to ionizing radiation. Few studies to date have had adequate statistical power to detect effects of the magnitude expected based on animal data, and most have not been of low-dose, protracted exposures associated with nuclear accidents and their aftermath. Although, to date, scant use has been made of the new genomic technologies, in Chernobyl-exposed areas of Ukraine and Belarus, excess minisatellite mutations have been seen in children born after the accident. We propose a study of parent-child trios in which at least one parent was exposed to Chernobyl radiation as a clean-up worker (mean dose >=100 mGy) and/or evacuee from a contaminated area (mean >= 50mGy). The specific aims are to investigate the transgenerational and de novo mutation rates of the spectrum of genetic variants in trios, in particular looking at effects in children and mapping them to possible parental origin of the chromsome. Together with long-term collaborators at the Research Center for Radiation Medicine (RCRM) in Kiev, epidemiologic data will be collected for up to 450 trios of parents with preconceptional doses and their unexposed offspring. We will use state-of-the-art genomic technologies to characterize the landscape of the genomes of the trios to determine whether parental radiation exposure is associated with genetic mutations transmitted to the offspring, by examining de novo mutation rates, minisatellite mutations, copy number alterations, and variations in telomere length. The analysis will be conducted in peripheral blood and/or buccal samples (when blood is not available) from complete father-mother-child trios. Doses to the gonads from the time of the accident to the time of conception will be reconstructed for all parents using existing records supplemented by interview data. Trio subjects will be selected from representative populations exposed to radiation from Chernobyl who are under active follow-up in the Clinico-Epidemiologic Registry at RCRM. To help identify specific effects of paternal and maternal radiation exposure, we will initially select sets of trio subjects in five categories: (1) exposed father, unexposed mother; (2) unexposed father, exposed mother; (3) both parents exposed; (4) both parents unexposed; and (5) a group of high dose emergency workers with acute radiation syndrome. All trio members will be invited to the RCRM outpatient clinic for collection of a 20 ml blood sample (or buccal cells for those who refuse phlebotomy). Both parents will be asked to complete a general questionnaire to obtain demographic and lifestyle data. Then one or both will complete detailed dosimetry questionnaires, based on forms used in previous collaborations with RCRM and administered by specially trained interviewers. Once 50 trios have been recruited (10 from each of the 5 exposure categories), we will conduct an interim evaluation of participation rates, sample collection and quality, and dose reconstruction in order to modify the protocol as needed. The analytical approach will be to correlate the extent, especially for de novo events of genetic alterations in the offspring with parental preconceptional radiation dose overall and by parental origin. The statistical power in relation to de novo mutations is very high, in excess of 90%, but somewhat lower for trends in minisatellite mutations. Study findings will contribute importantly to knowledge of the heritable effects of moderate- and low-dose radiation exposure in humans and to radiation risk projection. Eventually data from the Trio Study may be shared with the international community through dbGap.
Background: - PIK3CA-related overgrowth spectrum (PROS) is caused by changes in the PIK3CA gene. This gene makes a protein that communicates with other proteins in the body to cause cells to grow. Alterations in PIK3CA change the chemical signals in the body and cause overgrowth in fatty, vascular and other tissues. Sirolimus is a drug that reduces the signals sent by one of the proteins in this chemical signaling pathway. Researchers want to learn whether the drug sirolimus can reduce or stabilize some of the overgrowth that patients with PROS experience. Objectives: - To measure how the overgrowth of patients with PROS changes over time and whether taking a drug called sirolimus can reduce or stabilize a person s overgrowth. Eligibility: - People ages 3 to 65 years old with a confirmed mutation or alteration of the PIK3CA gene in the person s affected tissues (a somatic mutation). Design: - Participants will be screened with medical history and genetic counseling. - First 6 months: Participants will have their overgrowth monitored. - Next 6 months: Participants will take sirolimus once or twice a day. - Participants will have to visit the clinic several times, and stay in the area for 4 to 5 days each time. - Participants will have a one month-long visit to the clinic. - During clinic visits, participants will have: - Blood and urine tests. - Photographs of their physical features. - Scans, including an MRI and DEXA, and possibly x-rays and CT scans. - For the MRI and CT scans, participants will lie in a machine that takes pictures of their body. - The DEXA involves a small amount of radiation. - They may have: - Non-invasive heart function tests. - Lung function tests. - Participants will have several blood and urine tests between visits. - Participants will complete surveys and keep a diary of their treatment and side effects. - Participants may visit other health specialists or undergo other tests based on side effects. - One month after stopping the study drug, participants will have 1 clinic visit.
Preimplantation genetic diagnosis (PGD) is an assisted reproductive technology (ART) by which embryos, created through in vitro fertilization (IVF), can be screened for genetic conditions or traits before they are implanted into a woman s uterus. Within the past few years, a controversial non-medical use of PGD has gained recognition as having possible significant ethical implications. Non-medical sex selection (NMSS) describes the use of PGD technology to choose the sex of a child for social, as opposed to medical, reasons. In the US and a select few other countries, it is legal to use NMSS for family balancing, or the intentional selection of an underrepresented sex to balance a family where the majority of the children are of one sex. Proponents of family balancing believe that NMSS is an expression of reproductive autonomy and is ethically acceptable on those grounds. Opponents are more likely to cite beneficence (toward the existing children and the potential future child) and justice (resource allocation and access, for example) as the basis for concerns around NMSS and family balancing specifically. In the US and other countries, healthcare providers (HCPs) are often the gatekeepers to this technology. There is little research exploring the experiences of HCPs with PGD and NMSS. The Moral Experience framework (Hunt and Carnevale, 2011) is useful for understanding the potential concerns of HCPs as well as their feelings and behaviors evoked by lived and hypothetical experiences around NMSS. Also of interest is how HCPs feel that decisions about NMSS are made and their preferences as to how they should be made. Finally, there is concern that NMSS may be the first in a line of non-medical uses for PGD and that a slippery slope toward what some describe as designer babies will follow. We are interested in eliciting the traits that HCPs believe are hypothetically appropriate or inappropriate for PGD and how they make the distinction. Interviews with HCPs (OBGYNs and reproductive endocrinologists) on these topics will be transcribed and subjected to thematic analysis in order to identify common themes. An understanding of the experiences and attitudes of this stakeholder population can help clarify current issues at individual, societal, and global levels and future directions for research and policy....
The purpose of this research study is to examine whether specific genes (e.g. SLC16A11) affect how human beings respond to food and a medication that is commonly used to treat type 2 diabetes. The food the investigators will be studying is specially prepared to contain protein, carbohydrate, and fat. The drug the investigators are studying is metformin. The investigators hypothesize that physiological responses to the meal and to the medication will differ between carriers and non-carriers of genes associated with type 2 diabetes.
Background: - Previous research has shown that a person s genes can influence how they respond to alcohol. But researchers do not yet know all the genes that might be involved. Objectives: - To identify genes that are related to how non-alcoholic individuals respond to alcohol. Eligibility: - Healthy people between 21 and 30 years of age who have no history of alcohol or drug dependence. Design: - The study requires one or two 9-hour visits to the National Institutes of Health Clinical Center. - Participants must not take any medicines (except birth-control pills for women) for at least 3 days before the visit. They must not drink alcohol for at least 2 days before the visit. - Screening includes a medical history, physical exam, and a urine test for drugs of abuse. - Participants will be given alcohol over about 2.5 hours. This will have about the same effect as having three to four drinks. Frequent breathalyzer tests will check breath alcohol level during the infusion. - Before and during the infusion, participants will complete questionnaires about mood and feelings. Other tests will study thinking, balance, judgment, and risk-taking. Blood samples will be collected four times during the infusion. - Participants will have breakfast at the start of the visit (around 8:00 AM). They will have a snack before the start of the alcohol infusion (around 10:45 AM). Lunch will be served after the alcohol infusion is complete (around 2:20 PM). After the tests, those in the study will have to stay in the Clinical Center until their breath alcohol level falls below 0.02%. This can take up to 2.5 hours. A final blood sample will be drawn at that time. Participants will not be able to drive themselves home after the study visits. Also, they should not take any medicines or operate any machinery for at least 2 hours after leaving NIH.
The objectives of the current study are to identify and evaluate new prognostic non-invasive and serological markers in patients with pulmonary hypertension. The focus will be on L-arginine metabolism and to clarify its influence on endothelial function.
Background: - Congenital malformations, sometimes called birth defects, occur because of a difference in early human development. There are many different types of congenital malformations, and some of these can be caused by changes in genetic material. Researchers are interested in studying individuals with these congenital malformations to better understand the causes and the effects of certain congenital malformations. Objectives: - To understand more about what causes congenital malformations that arise in early human development. - To learn if genetic causes can be found to explain why a person has a congenital malformation. Eligibility: - Individuals who have been diagnosed with a congenital malformation. Design: - Participants will be seen at the National Institutes of Health for a series of visits over 3 to 4 days. Participants will be asked to provide copies of past medical records and test results for review, and will be asked questions about pregnancy/prenatal history, birth, newborn, medical, developmental, and family history. - Parents or siblings of participants may also be asked to provide information for research purposes. - Participants may have additional medical evaluations as part of this study, including any of the following tests: - Physical examinations - Other consultations as clinically indicated - Blood samples for genetic testing - Tissue biopsy for genetic testing - Photographs of affected areas, such as front and side views of the face and other body parts that may be involved in a congenital malformation, like the hands and feet. - Other tests as indicated by a specific malformation, such as organ ultrasounds. - No additional invasive testing, testing requiring sedation, or testing involving radiation is planned for this protocol. These tests, if performed, would involve a separate consent....