Introduction Flashcards
_______ is the study of chromosome and genomic structure and function with a focus on the behavior of chromosomes during meiosis and mitosis
Cytogenetics
_______ aka ______ ______ mutations are inheritable
constitutional, germ line
________ mutations are acquired and not inheritable
somatic (acquired)
_______ ________ in 1882 is credited with the discovery of chromosomes
Walther Flemming (tumor cells in mitosis)
The 30 nm fiber describes a well-characterized condensed state of ________?
chromatin
____________(s) and ____________(s) are constitutive heterochromatin that is genetically inactive, repetitive DNA
Centromeres and telomeres
The ____ chromosome is facultative heterochromatin that is reversibly activated and
inactive
X
___________ cluster at periphery of nucleus during G1 and disperse in S
Centromeres
Gene _______chromosomes in center of nucleus while gene ______ chromosomes locate toward nuclear envelope
rich (center), poor (envelope)
___________ (s) interact with nuclear envelope to help anchor chromosomes
Telomeres
Heterochromatin is associated with tight _______ histone binding
H1
3 structures of metaphase chromosomes
metacentric, submetacentric, acrocentric
Light G-bands: contain more __________ (chromatin) and are ____-rich,DNA
euchromatin, GC-rich
Dark G-bands: contain more ___________ (chromatin) and ______-rich DNA
heterochromatin, AT-rich
Complex of proteins at the centromere to which the microtubules of the spindles attach
kinetochore
Telomere sequence
TTAGGG
Sister chromatids are joined together at the _______________
centromere
After each replication, the telomere shortens by ______ bp
100
Meiosis _______ generates diversity (thinking crossing over)
Meiosis I
At the end of meiosis ___________ sister chromatids separate
Meiosis II
Male meiosis begins at _____________
puberty
It takes ~ ______ days to mature a sperm cell, about ______ days are spent in meiosis
64 days, 21 days
About ______ rounds of mitosis of the primordial germ cells produce the
diploid oogonia in a follicle
20
In females Meiosis II occurs at _______, 10 to 50 years later
ovulation
By _____ month of fetal development oogonia have developed into primary
oocytes, suspended in Prophase I
3rd
Specialized egg phase where they are suspended in prophase I
dictyotene
Egg meiosis II requires ___________
sperm penetration
_________________ is considered essential for proper chromosome segregation of homologues
recombination
_____ to _____% of clinically recognized pregnancies are chromosomally abnormal
7-10%
The X and Y chromosomes pair at _____ on the p arms and _______ on the q arms
PAR1, PAR2 (pseudoautosomal regions)
Aneuploidy in human zygotes ______ to ______%
5-25%
Nondisjunction in meiosis ______ results in heterodisomy and nullisomy
meiosis I
Ploidy of humans with 69 and/or 92 chromosomes
polyploidy
Nondisjunction in meiosis ______ results in isodisomy
meiosis II
Ploidy of gamete cells
haploid
Ploidy of humans with 69 chromosomes
triploid
______ is the number of homologous chromosome sets present in a cell or
organism
ploidy
Ploidy with incomplete sets of chromosomes
Aneuploidy (2n-1)
_______ only:
Paraffin embedded samples
Touch preps of tissue
Cytospin slides
FISH
Syndrome associated with deletion of 4p?
Wolf-Hirschhorn
Wolf-Hirschhorn phenotype
microcephaly
micrognathia
short philtrum
prominent glabella
ocular hypertelorism
shield faces
dysplastic ears and periauricular tags
growth restriction
intellectual disability
muscle hypotonia
seizures
congenital heart defects
FISH results on interphase cells can be reported in ______ to _____ hours
24 to 48
SNP microarray can be used to detect copy neutral ________
LOH, loss of heterozygosity (uniparental disomy)
Four things DNA microarrays cannot detect
- Balanced rearrangements
- specific mutations
- trinucleotide repeats
- low level mosaicism (10-15%)
SNP microarray has a resolution of _____ KB
5
Molar pregnancies with ______ contributions lack fetal development and have placental abnormalities
diandric (two sets of paternal chromosomes)
69, XYY or 69, XXX moles are _________ moles
partial moles
46, XX moles are ________ moles
complete (complete uniparental disomy)
Completes moles (46, XX) from dispermy are associated with what malignancy?
choriocarcinoma
FISH and ____________are both assessed on interphase chromosomes
CMA (chromosomal microarray)
Year ______ Mendel published his laws of inheritance developed from pea breeding
1866
In 1903 ______ and _______ posited chromosomes as carriers of genetic information (genes)
Boveri and Sutton
1909: ______describes the first inborn error of metabolism - alcaptonuria (homogentisic oxidase deficiency)
Garrod
_______: Beadle and Tatum develop the one-gene-one-enzyme (protein) theory
1941
1944: DNA is transforming factor. _____ et al. studied pneumococcus
Showed that infectious characteristics can be transferred between organisms
Avery
________is the year sickle cell anemia determined to be inherited
1948
________: Watson and Crick describe the structure of DNA
1953
Three technical improvements led to this discovery of 46 human chromosomes:
1. Use of ________ – stimulates T cells
2. __________ treatment causing the nucleus to swell and burst
3. Use of _________ to stall mitotic cells
- PHA - phytohemagglutinin
- hypotonic
- colchicine
_________ discoverer of trisomy 21
Marthe Gautier/ Jerome Lejeune
_______ is the year Peter Nowell discovers “Philadelphia chromosome” responsible for chronic myeloid leukemia
1960
1973:______ ________ discovers that the Ph+ chromosome is a translocation between chromosomes 9 and 22
She also identified translocation between chromosomes 8 and 21 in acute myelogenous leukemia, and between 15 and 17 in promyelocytic leukemia
Janet Rowley
__________ is the year “Rapid” sequencing methods by Sanger and Maxam & Gilbert
1977
1976: Kan, Golbus and Dozy publish first application of a DNA probe in the prenatal diagnosis of a genetic disease ______ _______ ______
sickle cell anemia
______: Kerry Mullis envisions PCR
1985
