UNIT I: (Lesson 1) INTRODUCTION TO CYTOGENETICS Flashcards
Lesson 1 : Cytogenetics Development and Importance
A branch of genetics that
studies the
structure of
DNA within
the cell
nucleus.
Cytogenetics
It is the studies the
number and morphology of
chromosomes.
Using
chromosome banding
techniques (classical
cytogenetics) or hybridization
fluorescently labeled probes
(molecular cytogenetics).
Cytogenetics
Fluorescently labeled
probes (molecular
cytogenetics) is shown
Cytogenetics
What are the 3 summarized Cytogenetics Development?
(Ferguson-Smith,2015)
A.Cell discovery
B.Chromosome structure and components discovery
C. Human cytogenetics emergence
Who observed the section of cork by a primitive type of microscope and found that it was made up of small hollow units like honey comb. He termed the structural unit as cell.
1665
Robert Hooke (1635-1703)
Who published microscopic anatomy of plants and advanced a theory that the stamen corresponds to male, while pistil corresponds to female reproductive organ.
1672
Nehemiah
Grew (1628-1711)
Who improved the microscope by the technique of grinding the lens. He reported the studies on free cells such as protozoa and bacteria and thus opened the door to a new world of microorganisms. He also studied blood cells.
1674
Anthony van Leeuwenhoek (1632-1723)
Who showed the presence of sex in plants. He demonstrated that in maize, seeds are not produced unless pollen is applied to the pistil. He concluded that pollen is the male element, while pistil is the female element.
1694
Rudolf Jacob Camerarius (1665-1721)
Who published the information on his work of plant hybridization. He made hybrids between different varieties of tobacco and between some plant genera. By using reciprocal crosses, he showed the equal contribution of male and female parents to their offspring.
1761-1766
Joseph Gottlieb Kolreuter (1733-1806)
Who proposed a theory of evolution known as theory of inheritance of acquired characters:
- Variation in an individual is brought about by:
(a) conscious effort,
(b) reaction to environment, and (c) use and disuse of the organ. - Heredity carries forward the changes that are acquired during the life time of the individual.
1809
Jean Baptiste Lamarck (1744-1829)
Who studied plant cells and discovered nucleus in Tradescantia. He described it as a central feature of living cells?
1828
Robert Brown (1773-1858)
Who described cell division and showed that cells arise through partition walls formed between preexisting cells?
1835
Hugo von Mohl (1805-1872)
Who put forth the cell theory on the basis of accumulated experimental results:
* The cell is the smallest structural element of a multicellular organism and as a unit, it is itself an elementary organism.
* In a multicellular organism, every cell has a specific function to perform, and represents a working unit.
* A cell can only be produced from another cell by cell division.
1838-1839
Matthias Jacob Schleiden (1804-1881) and Theodor Schwann (1810-1882)
In the Brief History of Cytogenetics, who is the 1st discovered chromosomes in pollen?
(1842) Karl Nägeli
Who introduced aniline staining to observe chromosomes during cell division?
(1870) Walther Flemming
Who coined the term “chromosome” after staining techniques had been developed?
(1888) Waldeyer
Who derived an estimate of 48 chromosomes using images of nuclei reconstructed from thin sections of human testicular tissue embedded in paraffin and stained with iron
hematoxylin?
(1923) Theophilus Painter
In what year, Cytogenetic technique improvements (use of colchicines to
arrest cells in metaphase)
1950
Who showed that human cells have 23 pairs of
chromosomes?
1956 Tjio and Levan
In what year, peripheral leukocyte culture method of Moorehead et al. was
adopted by many cytogeneticists
1960
Who developed the hybridization techniques in 1960s?
Joseph Gall and Mary Lou Pardue
In 1865, who discovered the “paired factors”?
Mendel
Mendel’s Laws:
- “paired factors” are inherited
- “paired factors” segregate during gamete formation
- “paired factors” independently sort
Who discovered the Chromosome theory of inheritance?
1902,Sutton & Boveri
Chromosomal Theory of inheritance:
- Chromosomes occur in pairs & are inherited from parents(the paternal & maternal chromosome)
- Chromosomes segregate in gamete formation (haploid)
- Chromosome pairs segregate independently
First genetic linkage map, polytene chromosomes isolation from fruit fly and first plant cytogenetics:
- Polytene chromosomes were first discovered in insects (Balbiani 1881)
- Morgan, Sturtevant, Bridges and Muller made the 1st genetic linkage maps from fruit fly
- 1920, Cyril Darlington pioneered plant cytogenetics
In what year, DNA and not protein in chromosome is the heredity material (genetic transformation expt.)
In Chromosome Components & Structure Discovery
1944
In Chromosome Components & Structure Discovery, who discovered the amount of nitrogen base in chromosome (Chargaff’s rule)?
Chargaff
1950
In Chromosome Components & Structure Discovery, who iscovered the double helix?
Watson and Crick
1953
In Chromosome Components & Structure Discovery, in what year is the Discovery of the genetic code in protein synthesis?
1961
(Crick, Brenner et al., 1961)
True or False: The first report of CGH analysis was by Kallioniemi and colleagues in 1992 at the University of California, San Francisco, who utilized CGH in the analysis of solid tumors
True
True or False: The implementation of array CGH, whereby DNA microarrays are used instead of the traditional metaphase chromosome preparation, was pioneered by Solinas-Tolodo et al. in 1997 using tumor cells and Pinkel et al. in 1998 by use of breast cancer cells
True
True or False: In Emergence of Human Cytogenetics, This enabled detection of numerical chromosome aberrations like trisomy 21 in Down syndrome
True
How many X in Turner syndrome?
45
How many XXY in Klinefelter syndrome?
47
True or False: Philadelphia chromosome in a patient with chronic myeloid leukemia.
* It was also reported that cells cultured from amniotic fluid could be used to determine the chromosome content of the fetus
True
