karyotyping
(KAYR-ee-oh-ty-ping)
A type of genetic test that analyzes the size, shape, and number of chromosomes in a sample of cells taken from blood, amniotic fluid, bone marrow, or other tissue. Changes in the number or structure of chromosomes may be a sign of a birth defect or genetic disease or condition, such as Down syndrome, Klinefelter syndrome, or Turner syndrome. Karyotyping may also be used to help diagnose certain types of cancer, such as leukemia, lymphoma, or myeloma, and/or help plan treatment.