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