Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

RCPsych Paper A > Genetics > Flashcards

Genetics Flashcards

1
Q

Mitosis stages

A

Prophase
Metaphase
Anaphase
Telophase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Prophase of mitosis

A

condensation of chromatic to discrete chromosomes
breakdown of nuclear envelope and formation of spindles at cellular poles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

metaphase of mitosis

A

alignment of chromosomes at metaphase plate in middle - equatorial alignmnet

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

anaphase of mitosis

A

separation of paired chromosomes followed by migration to opposite ends of the cell
separation preserves the chromosomal umber in the daughter cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

telophase of mitosis

A

chromosomes are backed into distinct new nuclei in the emerging daughter cells
cytokinesis (division of cytoplasm) also starts at this time

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

mieosis

A

meiosis I and meiosis II
produces 4 daughter cells, either with half the number of parent chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

how many chromosomes in human cell

A

46
(23 from each patent)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

how many autosomes in human cell

A

22 pairs of autosomes
2 sex chromosomes

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

metacentric chromosome

A

centromere in the middle
p and q arms equal

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

acrocentric / submetcentric chromosome

A

p and q arms not equal
centromere closer to one end

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

telocentric chromosome

A

centromere at the tail of a chromosome
not seen in humans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

holocentric chromosome

A

entire length of the chromosome acts as the centromere
not seen in humans

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

non-disjunction

A

failure of chromosome or chromatids to separate in meiosis, with one gamete receiving 2 copies of that chromosome and another with no copies

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Down’s syndrome

A

Trisomy 21
1:700 births

reduced materal AFP, increased betaHCG, increased nuchal fold thickness on USS

95% due to meiotic non-disjunction
5% robertsonian translocation
1% mosaicism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Edwards syndrome

A

trisomy 18
severe mental retardation, rocker bottom feet, low set ears, micrognathia, congential heart disease, clenched hands, prominent occiput

1:8000
often death within 1 year of birth
F>M 3:1

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Patau syndrome

A

Trisomy 13, 1:6000
severe mental retardation
microphthalmia
microcephaly
cleft lip/palate
coloboma eye
abnormal forebrain structures
polydactyly
congenital heart disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Metafemale

A

trisomy X

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Turners syndrome

A

80% from paternal X ch
1:2000 females
low hairline, broad chest, retronathism, webbed neck

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

Klinefelters

A

47 XXY

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

how many amino acids

A

20

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

how many possible codon combinations in genetic code

A

64

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

base pairs

A

AT
GC

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

DNA replication

A

production of new DNA copies from template DNA

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Transcription

A

synthesis of RNA from nuclear DNA
takes place in cell nucleus

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
introns
junk sequences - do not code for anything
26
splicing
removal of introns results in mRNA
27
translation
production of proteins from RNA takes place in the cytoplasm aided by ribosomes
28
exons
coding
29
point mutation
single base alteration in DNA usually substitutions could also be transition or transversion
30
frame shift mutations
deletion or insertion not in multiples of 3 codons leads to shift in triplet reading frame with variable results
31
silent mutation
no change in protein product
32
mis-sense mutation
new mutant codon specifies a different AA with variable effects on final protein product
33
non-sense mutation
new codon is a stop codon UUA UGA UAG results in non functional protein
34
translocation
exchange of chunks of genetic materials from one chromosome to another mutations occurring at 'larger' dimensions
35
reciprocal translocaiton
one segment exchanged for another segment among chromosomes
36
robertsonian transloation
non-reciprocal results in single fused chromosome from 2 acrocentric non homologous chromosomes small p arms are discarded, and metacentric fusion chromosomes results - single ch from the 2 only trivial loss of information viable and 'balanced' within the individual
37
unbalanced translocation / monosomy
when gametes are formed, only one of the 2 gametes can have the whole translocated metacentric fusion chromosome
38
DiGeorge / velocardiofacial
22q11.2 autosomal dominant deletion mild-mod LD facial deformities cleft palate malformed parathyroids - hypocalcaemia broad nasal bridge speech and swallowing problems >25% have psychosis
39
Williams syndrome
7q11 microdeletion hypercalcaemia at birth supra valvular aortic stenosis moderate LD disinhibited disposition speech artificially fluent hyperacusis
40
Smith Magenis Syndrome
17p11.2 microdeletion mod-severe LD self harming behaviour sleep disturbance self hugging
41
angelman syndrome
15q11-13 deletion maternally inherited developmental delay, low IQ, jerky movement eg hand flapping frequent smiling seizures
42
prader willi syndrome
15q11-13 deletion paternally inherited obesity, short stature, small libs, decreased IQ, hyperphagia and skin picking
43
cri-du-chat syndrome
chromosome 5p deletion feeding problems cat like cry poorly developed facial features
44
mendelian laws of inheritance
uniformity segregation independent assortment
45
law of uniformity
DD x dd = Dd two alternative alleles at one locus two homozygous parents all offspring are of uniform type
46
law of segregation
Dd x Dx = DD / Dd Dd / dd two heterozygous parents three possible types of offspring
47
law of independent assortment
DdHh (blue eyes brown hair) x ddhh (brown eye, black hair) = DdHh / ddHh / Ddhh / ddhh two loci with alleles D d H h double heterozygote x double homozygote parent 4 possible types of offspring, each with equal probability
48
incomplete penetrance
if patient have dominant disorder but does not manifest clinically gives appearance of gene skipping a generation
49
tuberous sclerosis
9q34 / 16p13 autosomal dominant 1:30,000 adenoma sebaceum, normal to severe MR, ash leaf macules, brain hamartomas, heart and kidney cysts
50
treacher collins syndrome
5q31 autosomal dominant 1:40,000 maxilla mandibular hypoplasia malformed pinna down slanting palpebrae mild to mod MR
51
apert syndrome
10q autosomal dominant variable MR cranio syntosis shallow orbits trapezoid mouth mitten hands and feet
52
noonan syndrome
Chr 12 autosomal dominant 1: 1500 mild MR short stature nuchal oedema/webbed neck pulmonary stenosis cryptorchidism
53
hurler syndrome
4p16 autosomal recessive 1:100,000 deteriorating IQ after age 2 coarse facies clouded cornea joint stiffness
54
lesch-nyhan syndrome
Xq 26-27 x linked recessive deficiency of enzyme HGPRT poor muscle control moderate mental retardation self mutilating behaviour - biting hyperuricaemia hyperuricosuria severe gout and kidney problems
55
mitochondrial inheritance
maternally inherited MELAS LHON (levers hereditary optic neuropathy)
56
anticipation
disease develops earlier in successive generations
57
fragile X syndrome trinucleotide repeat
CGG
58
friedreich ataxia trinucleotide repeat
GAA
59
huntington chorea trinucleotide repeat
CAGmyo
60
tonic dystrophy trinucleotide repeat
CTG
61
fragile X syndrome
males>female 2:1 trinucleotide repeat expansion CGG anticipation seen reduced IQ enlarged testes prominent ears protracting jaw high pitched voice
62
southern blotting
detection of specific sequence of DNA
63
western blotting
detection of specific protein after electrophoresis
64
northern blotting
detection of specific RNA after electrophoresis
65
PCR
minute amount of DNA can be amplified between two oligonucleotide primers denatured with heat then annealed
66
FISH
detect and localise specific DNA sequences on chromosomes isolated and inserted into plasmids which are vectors
67
concordance
a twin pair is concordant when both co twins have the same disease expression discordant if one has the disease and the other doesnt
68
heritability
main measure of genetic variation in polygenic traits the proportion that is genetic, not environmental the relative influence of genetic factors in defining the variance in a trait
69
schizophrenia heritability
80
69
bipolar heritability
>80
69
major depression heritability
40
70
generalised anxiety heritability
30
70
panic disorder heritability
40
71
phobia heritability
35
72
alcohol dependence heritability
60
73
big 4 personality traits in order of heritability
OECNA openness - 57% extraversion - 54% conscientiousness - 49% neuroticism - 48% agreeableness - 42%
74
hardy weinberg principle
in the absence of mutation, non-random mating, selection and genetic drift, the genetic constitution of the population remains the same from one generation to the next
75
when does hardy weinberg equilibrium not hold true
natural selection genetic drift gene flow consanguinity high frequency of mutations
76
genetic drift
gene frequency change caused by limitations in population size
77
gene flow
exchange of genes between populations due to migration or other social reasons, populations are not 'closed'
78
consanguinity
non-random mating occurs, and mutations are preserved within a closed pedigree autosomal recessive diseases are more often seen in consanguinous families
79
epistasis
gene-gene interactions between different alleles at different genes
80
locus heterogeneity
when same diseases phenotype can be caused by mutations in different loci
81
allelic heterogeneity
same disease phenotype resulting from different types of mutations at the same loci
82
pleiotropy
when a single disease-causing mutation affects multiple organ systems
83
monozygotic twins
identical twins when embryo is cleared during early development
84
dizygotic twins
fraternal twins share 50% of genes two ova two sperm
85
pairwise concordance
number of twin pairs who both have the disorder divided by total number of pairs
86
probandwise concordance
number of affected twins divided by total number of co-twins
87
LOD score showing statistical evidence of linkage
>3
88
LOD as evidence that two loci not linked
-2 or less
89
schizophrenia genes
NRG1 DTNBP1 G72 DAAO RGS4 COMT DISC1 dysbindin
90
bipolar disorder genes
BDNF DAO G72/G30 COMT
91
alzheimers genetics
APP (Ch 21) presenilin 1 (Ch 14) presenilin 2 (Ch 1) APOE
92
CADASIL
form of amyloid angiopathy that can present with alzheimers like features NOTCH3 is associated gene 19p13.1-13.2
93
frontotemporal dementia genetics
progranulin gene (PGRN) chromosome 17q21
94
parkinsons disease genes
PARK1, PARK4 - 4q21 alpha synuclein PARK2 6q25 parkin gene PARK8 12 cen LRRK2 gene PARK6 1p35-57 PINK1 mitochondria PARK7 1p38 DJ-1
95
autism sibling rate
2-8% 50x relative risk in siblings
96
autism monozygotic concordance
60%
97
autism dizygotic concordance
0%
98
ADHD first degree relatives risk
15-60% 2-6 relative risk
99
ADHD second degree relatives risk
3-9% 0.5-0.8 relative risk
100
ADHD heritability
70-80%
101
antisocial personality disorder heritability
60-70%
102
panic disorder lifetime prevalence
4.7%
103
approaches used in genetic clinics for genetic testing
direct testing - sample tested for certain genotype gene tracking - many family members tested to see whether patient has inherited high risk Ch from heterozygous parent. can be used if the exact genetic locus associated with a disease is unknown

RCPsych Paper A (3 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions