Karyotyping Flashcards
(23 cards)
What is karyotyping?
A cytogenetic technique used to visualize and analyze the complete set of chromosomes in an individual’s cells.
Involves staining chromosomes to produce a characteristic banding pattern for identification and analysis.
What do chromosomal abnormalities refer to?
Alterations in the number or structure of chromosomes, resulting in genetic disorders or diseases.
Common types include aneuploidy and structural abnormalities.
What is aneuploidy?
Changes in chromosome number, such as trisomy.
Example: Down syndrome.
What are structural abnormalities in chromosomes?
Alterations such as deletions, duplications, inversions, and translocations.
What is Fluorescence In Situ Hybridization (FISH)?
A molecular cytogenetic technique used to detect and visualize specific DNA sequences within chromosomes or cells.
How does FISH work?
Involves hybridization of fluorescently labeled DNA probes to complementary target sequences in the sample.
What are the applications of FISH analysis?
Diagnosis of genetic disorders, detection of chromosomal abnormalities in cancer cells, mapping of genes, and investigation of chromosomal structure.
What is the purpose of culturing cells in karyotyping?
To prepare cells for analysis by adding nutrients and antibiotics to prevent contamination.
What is the incubator temperature used during cell culture?
37 degrees Celsius.
What is the role of colcemid in karyotyping?
It prevents mitotic spindle formation during metaphase, causing cell arrest.
What is used to allow osmosis in karyotyping?
Hypotonic solution KCL.
What is the purpose of the fixative in karyotyping?
To lyse red blood cells, harden the cell membrane, and preserve white cells.
What is the staining method used in karyotyping?
Trypsin/Giemsa.
What is the process of analyzing metaphases in karyotyping?
Scan slides using a microscope and image acquisition software.
How are chromosomes classified in karyotyping?
In descending order of size and based on their centromeric index.
What designates the short arm of a chromosome?
p.
What designates the long arm of a chromosome?
q.
What are acrocentric chromosomes characterized by?
Having a very short p arm.
What does the chromosomal banding pattern allow for?
Precise location of genes and breaks.
What are numerical chromosomal aberrations?
Monosomy, trisomy, tetrasomy, polyploidy, others.
What are structural chromosomal aberrations?
Translocations, deletions, inversions, and complex rearrangements.
Fill in the blank: Chromosomes are numbered from 1 to ___ in karyotyping.
22.
True or False: The long arm of a chromosome is designated by ‘p’.
False.
