Genetic testing Flashcards
What is genetic testing?
The analysis of chromosomes, DNA, RNA, proteins, or other analytes to detect abnormalities that can cause genetic diseases.
What are the broad indications for genetic testing?
Prenatal diagnosis, heterozygote carrier detection, and presymptomatic diagnosis of genetic disease.
What is population screening?
Large-scale testing of populations to identify individuals who probably have a disease and those who do not
What is genetic screening?
Population screening for genetic variants that can cause disease in carriers or their descendants.
What are the key principles of screening?
Sensitivity (correctly identifying those with the disease) and specificity (correctly identifying those without the disease).
What are Mendelian disorders?
Disorders resulting from mutations in genes with high penetrance and varying expressivity, often leading to childhood or adult kidney phenotypes.
What is the purpose of newborn screening for inborn errors of metabolism?
To detect genetic diseases presymptomatically, such as sickle cell disease and other hemoglobin disorders.
What is heterozygote screening used for?
To identify carriers of autosomal recessive disorders, such as Tay-Sachs disease and β-thalassemia major.
What is presymptomatic diagnosis?
Testing at-risk individuals for genetic mutations to determine if they will develop a genetic disease, like Huntington’s disease.
What are the psychosocial implications of genetic screening?
Genetic screening can cause anxiety, stigma, and confusion over the results, which may not definitively diagnose a disease.
What is direct mutation analysis?
The detection of a disease-causing mutation, commonly used in genetic diagnosis.
What is the goal of prenatal genetic diagnosis?
To provide at-risk families with information to make informed pregnancy decisions and to prepare for the birth of a potentially affected child.
When is amniocentesis typically performed, and what does it involve?
Performed at 15 to 17 weeks of pregnancy, it involves using a needle to sample amniotic fluid for genetic testing.
What is CVS and when is it performed?
A prenatal diagnostic technique where fetal tissue is sampled at 10 to 11 weeks, providing earlier diagnosis than amniocentesis.
What is PUBS and its purpose?
A method to access fetal blood after the 16th week of gestation for prenatal genetic testing.
