UNIT 5: Chromosomal Aberrations Flashcards
(212 cards)
1
Q
t/f: Chromosomal mutations is commonly known as chromosomal aberrations
A
true
2
Q
these are variations from the wild-type condition in either chromosome structure or number
A
Chromosomal mutations
3
Q
t/f: Chromosomal mutations arise spontaneously or induced by chemical or radiation mutagens
A
true
4
Q
chromosomal abnormality: abnormal chromosome number, quantitative
A
Aneuploidy
4
Q
2 types of chromosomal abnormalities
A
Aneuploidy
Structural
5
Q
chromosomal abnormality: alteration, qualitative
A
Structural
6
Q
4 variations in chromosome structure
A
Deletion
Duplication
Inversion
Translocation
7
Q
2 types of Variation in Chromosome Number
A
Aneuploidy
Polyploidy
8
Q
t/f: monosomics/trisomics/nullisomics/tetrasomics are under polyploidy
A
false, aneuploidy
9
Q
3 categories of chromosome mutations
A
Chromosome rearrangements
Aneuploidy
Polyploidy
10
Q
Category of chromosome mutation:
overall chromosome number is unaffected but large pieces of chromosomes move altering the chromosome structure
A
Chromosome Rearrangements
11
Q
Category of chromosome mutation:
one or more individual chromosome pair has its number altered (either up or down) altering chromosome number
A
Aneuploidy
12
Q
Category of chromosome mutation:
down syndrome, klinefelter, turners, 45, 47
A
Aneuploidy
13
Q
Category of chromosome mutation:
humans with 3n, 4n, etc.
A
polyploidy
13
Q
t/f: aneuploidy is better than polyploidy
A
true
14
Q
Category of chromosome mutation:
one or more complete chromosome sets are added
A
Polyploidy
15
Q
when a set of chromosomes do not properly separate leaving two sex cells with an extra chromosome or one less chromosome developing a chromosomal disorder
A
Nondisjunction
16
Q
results when an error occurs during meiosis, specifically non disjunction.
A
aneuploidy
16
Q
most often caused by error during cell division, mitosis and meiosis
A
chromosomal aberrations
17
Q
a pair of homologous chromosomes has failed to separate or segregate at anaphase so that both chromosomes of the pair pass to the same daughter cell
A
nondisjunction
18
Q
t/f: non disjunction occurs most commonly in mitosis
A
false, meiosis
19
Q
t/f: nondisjuction in mitosis produces mosaic individual
A
true
20
Q
t/f: structural chromosomal aberrations can result in an aneuploidy
A
true
21
Q
when part or all of a chromosome is missing, turned upside down, duplicated, or attached to another chromosome
A
structural chromosomal aberrations
22
t/f: when structural chromosomal aberrations occur after meiosis, two copies or no copies is passed down ending up with monosomy or trisomy
true
23
when two or more different cell lines in one person and occurs after non disjunction in a mitotic cell division
mosaicism
24
t/f: mosaicism results in one line of cells with chromosomal aberration white other lines may stay unchanged
true
25
chromosomal mutation that results in the doubling of a segment of a chromosome
duplication
25
3 forms of duplication
1 Tandem Duplication
2 Reverse Duplication
3 Terminal Tandem Duplication
26
meaning of ISCN
International System for Human Cytogenomic Nomenclature (ISCN)
27
according to ISCN, dup means
duplication of parts of a chromosome
28
dup(17p12) causes ____ disease
charcot-marie-tooth type 1A
28
meaning of dup(17p12)
duplication of chromosome 17, region 1, band 2
29
when a part of chromosome is double
duplication
30
types of duplication
tandem duplication
displaced duplication
reverse duplication
31
type of duplication: one right after the other
ABCD*EFGH -> ABCD*EF [EF] GH
tandem duplication
32
type of duplication: goes to another place but still in the same chromosome
ABCD*EFGH -> AB [EF] CD* EFGH
Displaced duplication
33
type of duplication: where the duplicated region is inverted
ABCD*EFGH -> ABCD*[FE] EFGH
reverse duplication
34
t/f: individuals can only be homozygous for duplications
false, can be homozygous or heterozygous
35
when heterozygous for duplication, problems arise during ___ of meiosis and synapsis
prophase 1
36
when heterozygous for duplication, one duplicated region must ___ to allow synapsis to occur
loop out
37
due to ___, duplications may have significant effects on an individuals's phenotype
unbalanced gene dosage
38
we are evolved to have ___ alleles for each gene
two alleles
39
t/f: duplications also allow new genes to be born with novel functions
true
40
t/f: when a gene duplicates the new duplicated gene cannot be free to mutate and evolve while the original gene continues carrying on normal functions allowing evolution to proceed with little risk to the individual
false, it can
41
duplication allowed fetal hemoglobin to evolve, making placental ___ reproduction possible
in utero reproduction
42
t/f: because of mutations, species are not evolving
false, they are evolving because of mutations
42
involves the loss of a segment of a chromosome
deletions
43
t/f: in deletions, deleted segment is only located in a specific site along the chromosome
false, may be located anywhere along the chromosome
44
t/f: breaks in chromosome for deletions may be caused by agents such as heat, ionizing radiation, viruses, transposable elements) or by errors in recombination
true
45
which molecular test is used for detecting copy number loss and copy number gains
CGH
46
t/f: chromosomal deletions may or may not span a centromere
true
47
if a deletion spans a centromere, it results to ____
acentric chromosome
48
3 types of deletions
terminal deletion
intercalary/interstitial deletion
microdeletion
49
type of deletion: a deletion that occurs towards the end of a chromosome
terminal deletion
49
type of deletion: a deletion that occurs from the interior of a chromosome
Intercalary/interstitial deletions
50
type of deletion: a relatively small amount of deletion (up to 5Mb that could include a dozen genes)
microdeletion
51
usually found in children with physical abnormalities.
microdeletion
52
a large amount of deletion in children would results in immediate ____ also called ____
abortion, miscarriage
52
the loss of a region or segment from a chromosome
chromosome deletions
53
ABCD*EFGH -> ABCD*GH
Chromosome Deletions
54
if the deletion is large enough, it can be detected in a karyotype as _____ chromosome
shortened chromosome
55
deletions also result in ____ during prophase 1 to allow alignment during synapsis
looping out
55
t/f: the effect of a deletion depends solely on what genetic information was deleted
true
56
t/f: deletions are lethal, and are completely symptomatic
false, others are completely asymptomatic
57
if the deleted region includes the centromere, the mutated chromosomes will ____ during mitosis or meiosis and are usually ___ by the cell during cell division
not segregate, lost
58
deletions are highly detrimental when an individual is ___ for the deletion
homozygous
59
t/f: homozygous for the deletion would be the complete absence of that genetic information
true
60
deletions in heterzygous individuals cause ____ like duplications
gene imbalance
61
difference between the gene imbalance cause by duplications and deletions in heterozygous
duplications: too much
deletions: not enough
62
t/f: recessive alleles does not express more readily when there are deletions
false, it is express more readily
63
according to ISCN, minus (-) is for ____ and del is for ____
minus (-) = chromosome deletions
del = deletions of a part of a chromosome
64
this results from a deletion of a number of pairs that is not evenly divisible by three
frameshift mutation
65
causes all of the codons occuring after the deletion to be read incorrectly during translation, producing altered or nonfunctional protein
frameshift mutation
66
a deletion that is evenly divisible by three is called ____
in frame deletion
67
what are the 3 major genetic disorders caused by deletions
1. male infertility
2. duchenne muscular dystrophy
3. cystic fibrosis ( ΔF508)
68
deletion of part of the short arm of chromosome 5 results to ____
cri du chat syndrome
69
deletions in the SMN-encoding gene causes _______
spinal muscular atrophy
70
t/f: spinal muscular atrophy is the most common genetic cause of adult death
false, infant death
71
microdeletions are associated with conditions (3)
Angelman Syndrome
Prader-Willi syndrome
DiGeorge Syndrome
72
syndromes associated with microdeletions adn genomic imprinting
Angelman syndrome
prader-willi syndrome
73
t/f: same microdeletion can cause two different syndromes depending on which parent the deletion came from
true
74
human disorders caused by deletions: 5p-
cri du chat syndrome
75
human disorders caused by deletions: 13q-
retinoblastoma
75
human disorders caused by deletions: 11q-
wilms tumor
76
human disorders caused by deletions: 15q-
prader-willi syndrome
77
infants have catlike cry, some facial anomalies, severe mental retardation
cri du chat syndrome
78
kidney tumors, genital and urinary tract abnormalities
wilms tumor
78
cancer of the eye, increased risk of other cancer
retinoblastoma
79
infants: weak slow growth; children and adults: obesity, compulsive eating
prader-willi syndrome
80
deletion in the short arm of chromosome 5
cri du chat syndrome
81
cri du chat syndrome occurs in every __ out of 100,000 births
1
81
mentally retarded, with defects on facial development, gastrointestinal malformations, and abnormal throat structures
cri du chat syndrome
82
cry of the cat
cri du chat
83
deletions in the long arm of chromosome 15
prader-willi syndrome
84
prader willi syndrome occurs when there is deletions between the bands of ___ and ___ of chromosome 15
q 11 and q 13
85
affected infants of prader willi syndrome has ____ reflex
poor sucking reflex
86
by age ____, children of prader willi syndrome become compulsive eaters
5-6
87
poor sexual development in males, behavioral problems and mental retardation
prader willi syndrome
88
delayed development, problems with speech and balance, intellectual disability, and sometimes, seizures
angelman syndrome
89
t/f: people with angelman syndrome often smile and laugh frequently and have happy excitable personalities
true
90
in angelman syndrome, developmental delays begin between about ___ and ___ months of age
6 - 12 months
91
in angelman syndrome, seizures begin between ages ___ and __ years old
2-3 years old
92
t/f: people with angelman syndrome have short life span
false, they have close to a normal life span
93
t/f: angelman syndrome cannot be cured
true
94
in angelman syndrome, the loss of a gene called ____ is associated with light colored hair and fair skin
OCA2
95
the OCA2 gene is located on the segment of chromosome ___ that is often deleted in people with disorder
15
96
it is a chromosomal mutation that results when a segment of a chromosome is excised and then reintegrated in an orientation 180 degrees celsius from the original orientation
inversion
97
2 forms of inversion
pericentric inversion
paracentric inversion
98
according to ISCN,abbreviation "inv" means
inv = inversions
99
for inversions to happen, the DNA must break in ___ on either side of the inverted segment
two places
100
inversion that does not include the centromere
paracentric inversions
101
inversions that include the centromere
pericentric inversions
102
t/f: inversions played an active role in the evolution of humans
true
103
humans differ from chimps greatly in ____
inversions
104
in what chromosome does chimps and humans differ greatly in inversions, and what type of inversion
chromosome 4, pericentric inversion
105
karyotypic differences between humans and chimpanzees include ___ pericentric inversions
9 pericentric inversions
106
the breakpoints of the inversion that distinguishes human chromosome 4 (HSA4) from its chimpanzee counterpart were identified by ____ (___) and _______
flourescence in situ hybridization (FISH)
comparative sequence analysis
107
breakpoints at ____ and ___, do not disrupt the protein coding of a gene, although they occur in regions with an abundance of LINE and LTR-elements
HSA4p14 and 4q21.3
108
if an inversion breaks a gene in half, moving half of that gene to another part of the chromosome will render that gene _____
inactive
109
t/f: chromosome inversions usually do not cause detrimental effects
false, if the gene inverted was important, it will be
110
t/f: many genes are regulated based on their position on the chromosome
true
111
what do you call the effect where you change a gene's position and it turn you change its regulation
position effect
112
individuals ____ for inversion require some super-funky loops in order to allow synapsis in meiosis
heterozygous
113
genes are regulated, two things may happen in position effect what are these two
1. far from transcription factors
2. close to transcription factors
114
there is a change in the position of chromosome segments and the gene sequences they contain
translocation
115
t/f: in translocation there is gain or loss of genetic material
false, there is none
116
2 kinds of translocation
intrachromosomal
interchromosomal
117
kind of translocation: change in position of a chromosome segment within the same chromosome
intrachromosomal
118
kind of translocation: transfer of a chromosome segment from one chromosome into a nonhomologous chromosome
interchromosomal
119
t/f: translocations are usually non homologous
true
120
according to ISCN, what is the meaning of t(A;B)(p1;q2)
t=translocation
A= chromosome A
B = chromosome B
p = short arm
q = long arm
numbers = regions, bands, and subbands
121
regions, bands, and sub bands are seen when staining the chromosome with a ____
staining dye
122
when DNA moves from one chromosome to another non homologous chromosome, a ____ has occurred
translocation
123
t/f: translocations may not occur in a single chromosome
false, it can also
124
translocation where DNA only moved in one direction
Nonreciprocal translocation
125
translocation where DNA is exchanged in both directions
reciprocal translocations
126
t/f: non reciprocal translocations are more common than reciprocal
false, reciprocal are more common
127
t/f: translocation is only between homologous chromosomes during meiosis
false, that is crossing over
128
t/f: chimps, orangutans and gorillas have 24 chromosomes
false, 48
129
t/f: translocations cause new linkage patterns thus changing how genes are inherited
true
129
t/f: translocations does not result in position effects
false, it results also
130
t/f: chromosome duplications often accompany translocations
false, chromosome deletions
130
2 types of interchromosomal translocation
reciprocal
non reciprocal
131
type of interchromosomal translocation: exchange of segments between two chromosomes
reciprocal
132
type of interchromosomal translocation: transfer of segment in one direction from one chromosome to another
non-reciprocal
133
when the short or long arms of same chromosome join at centromere and creates two copies of a large genetic region
isochromes
134
shows characteristic mirror image appearance of banding patterns extending in both directions from centromere
isochromes
135
joining of centromere occuring between chromosomes that have tiny short arms (acrocentrics)
robertsonian translocation
136
t/f: in robersonian translocation, there is no obvious lost in genetic information because the short arms contain repeated rRNA genes
true
137
involves reciprocal translocation between the long arm of chromosome 22 and chromosome 9
chronic myelogenous leukemia
138
transition of c-abl within the bcr
chronic myelogenous leukemia
139
results to uncontrolled replication of myeloblasts
chronic myelogenous leukemia
140
PML RARA is what type of gene
translocation gene
141
common disease in africa, virus induced tumor; malignant B cells secrete antibodies
burkitt's lymphoma
142
involves reciprocal translocation between chromosome 8 and 14 and activation of c-myc
burkitt's lymphoma
143
organism or cell has one or exact multiple of complete set(s) of chromosomes
euploidy
144
irregular distribution of sister chromatids during mitosis or of homologus chromosomes during meiosis
nondisjunction
145
type of aneuploidy: both members of a homologous pair are lost (46 to 44 or 2n -2)
nullisomy
145
4 types of aneuploidy
nullisomy
monosomy
trisomy
tetrasomy
146
type of aneuploidy: one chromosome is lost (46 to 45 or 2n - 1)
monosomy
147
type of aneuploidy: one chromosome is gained (2n + 1)
trisomy
148
type of aneuploidy: involves an extra chromosome pair (2n + 2)
tetrasomy
149
t/f: it is not possible for an individual to have multiple instances of aneuploidy and still have normal chromosome number
true
149
2n + 1 + 1
double trisomic
150
t/f: trisomy of the X chromosome cannot be tolerated in females
false, it is tolerated well
151
t/f: Y aneuploids are viable
true
152
___% of all successful concenptions spontaneously abort (miscarry)
30%
153
__% of these miscarried fetuses ahve chromosome mutations
50%
154
in humans, only __% of aneuploids survive to birth
3%
155
in mice, ___% of all conceptions are aneuploid
2%
156
t/f: most human aneuploids have X or Y chromosome aneuploidy
true
157
occurs ~1 in 25,000 to 50,000 live briths, mental retardation adn characteristic physical alternations, many have normal life expectancy
trisomy 8
158
t/f: trisomy 21 is tolerated better because it a small chromosome with fewer genes
true
159
syndrome: trisomic 21
down syndrome
160
syndrome: trisomic 13
patau
161
syndrome: trisomic 18
edwards
162
syndrome: XO, monosomic
turner
163
syndrome: trisomic XYY
normal
164
syndrome: XXY, XXYY,XXXY
klinefelter
165
wide skull flat back, epicanthic fold, iris spots, furrowed and protrudign tongue, congenital heart defects
trisomy 21
166
cleft lip and palate, small eyes, polydactyl (extra fingers and toes), mental and developmental retardation, severe malformation of the brain and nervous system
trisomy 13
167
most affected infants of trisomy 13 die before the age of ____
three months
168
life expectancy of edward syndrom
2-4 months
169
life expectancy of trisomy 13
50% die within first month, 95% three years
170
life expectancy of trisomy 8
may be normal life expectancy
171
t/f: males are mostly affected by edwards syndrome
false, females
172
multple congenital malformations, clenched fists, elongated skill, low set ears, retardations
edwards
173
leading risk factor for autosomal trisomy
maternal age
174
t/f: the integrity of primary oocytes increases as the women age
false, decreases
175
t/f: as a woman age, maternal selection becomes less effective
true
176
short and wide chested, webbed neck, underdeveloped breasts and rudimentary ovaries, absence of barr body, color blindness, narrowing of aorta
turner syndrome
177
t/f: klinefeltersyndrome features do not develop until puberty
true
178
males with poor sexual development, very low fertility, breast development
klinefelter syndrome
179
above average height, suffered personality disorders, below normal intelligence, violent criminal behavior
47, XYY
180
t/f: Y chromosome is essential for suvival
false, X chromosome
181
getting two chromsomes from one parent
uniparental disomy
182
cell is conceived trisomatic but loses a chromosome early on in development
uniparental disomy
183
chromosome lost came from the nondisjunctive parent, teh other two came from one parent
uniparental disomy
184
polyploidy is common in ____ and is the major driving force behind its speciation
plants
185
two types of polyploidy
autopolyploidy
allopolyploidy
186
type of polyploidy: all sets of chromosomes are from a single species
autopolyploidy
187
type of polyploidy: when polyploidy represents a hybridization between specieies with chromosome sets coming from different cells
allopolyploidy
188
t/f: allopolyploids are sterile and cannto cross fertilize but plants can
true
189
most common form of polyploidy
triploidy
190
(69, XXY), (69,XXX), (69,XYY)
triploidy
190
life expectancy of triploid infants
within a month
191
DNA duplication but no cell division is called
endomitosis
191
endomitosis results to ____
tetraploidy
192
___ of DNA and histones causes nucleosomes to pack tightly together
Methylation
193
___ results in loose packing of nucleosomes
Histone acetylation
194
Gene mutation/Chromosomal mutations:
alteration of the nucleotide of sequence of a gene
Gene mutation
