Cytogenetics

Cytogenetics studies chromosomes, including their structure, behavior, and abnormalities, using methods that examine them in cells.

Karyotype: An organized display of an individual's chromosomes, arranged by size, shape, and banding pattern. The karyotype is the central visual summary used to identify chromosome number and structure.
Chromosome: A DNA-protein structure that packages genetic material and transmits it during cell division. Chromosomes are the physical units examined by cytogenetic methods.
Constitutional cytogenetics: The study of chromosome variation present in an individual's germline and most body cells. It detects inherited or developmental chromosome changes in prenatal and postnatal testing.
Molecular cytogenetics: The use of molecular probes and genomic methods to study chromosomes in cells. It extends classical microscopy with targeted detection of DNA sequences and copy-number changes.
Aneuploidy: A chromosome-number state in which one or more chromosomes are present in abnormal copy numbers. Detecting aneuploidy is a major use of chromosome counting in clinical cytogenetics.
G-banding: A chromosome staining method that produces characteristic dark and light bands for identification. Its reproducible band patterns let laboratories recognize chromosomes and large rearrangements.
Chromatin: The complex of DNA and proteins that packages the genome in a cell. Chromatin compaction determines how chromosomes appear and which regions can be examined.
Cancer cytogenetics: The analysis of chromosome abnormalities in cancer cells for diagnosis, classification, and treatment decisions. Acquired chromosome rearrangements can define cancer subtypes and guide clinical management.
Classical cytogenetics: Chromosome analysis based primarily on microscopy, staining, and cell culture. Its genome-wide view contrasts with molecular methods that target selected sequences or measure DNA dosage.
Translocation: A rearrangement in which a chromosome segment moves to a different chromosome or location. Balanced and unbalanced translocations can affect fertility, development, or cancer biology.

Linked from 11 pages