Comparative Genomic Hybridization (CGH)

A set of vocabulary flashcards covering key terms and concepts related to Comparative Genomic Hybridization (CGH) and its applications in detecting chromosomal abnormalities.

Copy Number Variations (CNVs)

Alterations in the DNA of a genome that result in a cell having abnormal copies of one or more sections of the DNA.

Comparative Genomic Hybridization (CGH)

A molecular cytogenetic method for analyzing copy number variations using hybridization techniques.

Deletions

A segment of DNA missing from the test sample when compared to the reference.

Duplications

A segment of DNA present in multiple copies in the test sample compared to the reference.

Hybridization

The process where labeled DNA from test and reference samples combine on metaphase chromosomes.

Denaturation

The process of separating double-stranded DNA into single strands to prepare for hybridization.

Fluorescence Signal Interpretation

Analysis of fluorescent signals to determine the presence of CNVs in DNA samples.

Green Signal

Indicates a greater quantity of test DNA compared to reference DNA, often reflecting deletions.

Red Signal

Indicates a greater quantity of reference DNA compared to test DNA, often reflecting duplications.

Balanced Hybridization

Condition where there are equal signals from both test and reference DNA, indicating no CNVs.

Cot-1 DNA

A DNA used to block or suppress repetitive sequences during CGH.

Fluorochrome

Fluorescent dye used to label DNA samples for detection during hybridization.

Spectral Karyotyping (SKY)

A technique that visualizes all chromosome pairs in different colors to identify chromosomal abnormalities.

Array CGH (aCGH)

An advanced version of CGH that uses DNA microarrays for higher resolution detection of CNVs.

Resolution

The ability of a method to detect small CNVs, with traditional CGH being relatively low (5-10 megabases).

Sensitivity

The capability of a method (like aCGH) to detect CNVs that may be missed by traditional methods.

Automation

The use of automated processes in aCGH to reduce human error and expedite sample processing.

Visualization

The process of observing hybridized DNA samples under a fluorescent microscope.

Molecular Cytogenetics

A branch of cytogenetics that uses molecular biology techniques to study chromosomes.

Tumor Cells

Cells that are often analyzed for changes in DNA content, particularly CNVs.

Research Tool

CGH was initially developed as a means to investigate genomic alterations in cancer research.

Chromosomal Microarray Analysis (CMA)

Another name for Comparative Genomic Hybridization, focusing on DNA microarrays.

Probe

A fragment of DNA or RNA used in hybridization to detect specific sequences.

Fluorescent Microscope

An instrument used to visualize labeled DNA under specific light conditions.

Metaphase Spread

A preparation of chromosomes that are stained and viewed under a microscope for analysis.

Hybridization Chamber

Moist environment where test and reference DNA are incubated during hybridization.

Counter stain

A dye used to improve the visualization of the hybridized DNA under a microscope.

Signal Intensity Ratio

The comparison of fluorescence signals from test and reference DNA indicating CNV results.

Technical Challenges

Specialized equipment and expertise required for CGH, complicating result interpretation.

Genomic Alterations

Changes in the structure or number of chromosomes that can be analyzed using CGH.

Chromosomal Abnormalities

Structural or numerical changes in chromosomes that can result in genetic disorders.

DAPI

A counter stain that binds to DNA, used during the visualization process.

Prenatal Gene Mutations

Mutations in genes that can be screened during fetal development.

Economic Consequences

Financial impacts caused by chromosomal genetic abnormalities in populations.

Diagnostic Tools

Advanced techniques such as FISH, CGH, and SKY used to detect chromosomal abnormalities.