Final answer:
Noninvasive prenatal genetic diagnosis typically utilizes a blood sample from the expectant mother to detect potential genetic conditions of the fetus, which is safer than more invasive methods like amniocentesis.
Step-by-step explanation:
Noninvasive prenatal genetic diagnosis typically uses a blood sample from the pregnant mother. This type of test can detect genetic conditions such as chromosomal disorders without the need for more invasive procedures like amniocentesis, where amniotic fluid is tested, or chorionic villus sampling, which tests tissue from the placenta. Noninvasive testing is possible because the mother's blood contains cell-free fetal DNA (cffDNA) that can be analyzed to gain information about the fetus's genetic health. Traditionally, genetic diseases have been diagnosed using DNA tests that determine carrier status for conditions like Fragile X and cystic fibrosis. These conditions and others that affect the chromosomes can be identified through the mother's blood, alleviating some of the risks associated with more invasive procedures. Genetic counselors play a crucial role in educating and supporting couples through the decision-making process and implications of genetic testing.