Cytogenetics 2-2
Cytogenetics
- branch of science concerned with how chromosomes related to cell behaviour particularly during meiosis and mitosis. Green 1968.
- Techniques used. Karyotyping. G banded chromosomes. Fluorescent in situ hybridization fish. Comparative genomic hybridization
- Chromosomes first observed by karl wilhelm 1842. Behaviour described by Fleming 1882.
- Karyotyping arrests chromosomes in metaphase during mitosis and studies them.
- used in
- study of drosophila by dobzhansky.
- Down syndrome patients add extra copy of chromosome 21. Lejuene 1951
- Turner syndrome extra X chromosome in males. Edward syndrome trisomy at 18 patau syndrome trisomy at 13.
- Paternity
- Gene mapping
- Banding technique. Q banding in 1960 to trace chromosome deletion and translocations.
- Fish technique greater probe and detailed study.
- Today with advanced tools like crisper, STR analysis we study chromosomes at DNA level and even manipulate them. Moving into molecular cytogenetics.
- Q -AT
- N - NOr
