Seminar/Lab 06: Molecular Basis of Gene Expression - Replication and Cytogenetics

Comprehensive vocabulary flashcards covering the molecular basis of gene expression, cytogenetic techniques, chromosome classification, and clinical applications as described in the lecture notes.

Cytogenetics

A division of genetics dealing with the study of chromosomes, focusing on their shape, number, and inheritance.

Q-bands

Bands visualized in a fluorescence microscope after staining chromosomes with a fluorochrome - quinacrine solution.

G-bands

Bands formed by mild proteolysis followed by Giemsa dye; dark areas contain many $AT$ pairs and heterochromatin, while bright areas contain many $GC$ pairs and euchromatin.

R-bands

Bands created by thermal denaturation followed by Giemsa dyeing, representing the negative of G lines.

C-bands

A staining technique that reveals constitutive heterochromatin.

T-bands

A staining technique used to reveal telomeres.

AgNOR

A method that allows the analysis of nucleolus organizers.

Group A

Classification for chromosomes $1$ - $3$, which are large metacentric chromosomes.

Group B

Classification for chromosomes $4$ - $5$, which are large submetacentric chromosomes.

Group C

Classification for chromosomes $6$ - $12$ and the $X$ chromosome, described as intermediate-length metacentric or submetacentric chromosomes.

Group D

Classification for chromosomes $13$ - $15$, which are intermediate-length acrocentric chromosomes with satellites.

Group E

Classification for chromosomes $16$ - $18$, which are short metacentric or submetacentric chromosomes.

Group F

Classification for chromosomes $19$ - $20$, which are very short metacentric chromosomes.

Group G

Classification for chromosomes $21$ - $22$ and the $Y$ chromosome; these are short acrocentric chromosomes, with $21$ and $22$ possessing satellites.

Aneuploidy

An abnormal number of chromosomes in a cell, such as in Down's syndrome, potentially predisposed by a mother's age after $37$ years.

Oncological Cytogenetics

The study of abnormal karyotypes in tumor cells to facilitate the identification and treatment of neoplastic diseases.

Bone marrow aspirate

The reference material for cytogenetic analysis in hematological neoplasms, including myelodysplastic syndrome and multiple myeloma.

Classical Karyotype Test Limits

Reveals structural changes covering an area of at least $10^6 - 10^7$ base pairs and only covers populations of dividing cells.

FISH

Fluorescence in situ hybridization; a molecular cytogenetics method.

CGH

Comparative genomic hybridization, used to detect changes within the genome.

MLPA

Multiplex Ligation-dependent Probe Amplification; a method of molecular cytogenetics.

SNP

Single Nucleotide Polymorphism; a molecular biology method used for genetic analysis.

Phytohemagglutinin

A reagent used in the preparation of cytogenetic samples to induce mitosis/culture peripheral blood cells.

Colchicine

A reagent used during cytogenetic preparation to arrest cells in the metaphase state of the mitotic cycle.

Trypsin

A reagent used for proteolysis (digestion) of chromosomes prior to staining to obtain a stripe pattern.

Karyogram

An image or systematic arrangement of the metaphase chromosomes of a single cell.

Karyotype

The number and type of chromosomes present in the nucleus of an individual, detailing cytogenetically detectable aberrations.

Ideogram / Idiogram

A diagrammatic representation of the human karyotype showing chromosome morphology.

Lionization

The process of $X$ chromosome inactivation, resulting in the formation of a Barr body in interphase cells.

Barr body

The condensed, inactive $X$ chromosome found in the nuclei of female mammalian cells.