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M2M Unit 2 > Week 1 > Flashcards

Week 1 Flashcards

1
Q

Penetrance

A

on/off switch

  • If person has mutation they either effected or not effected
  • NOT influenced by level of phenotype expression
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2
Q

Expressivity

A

dimmer function

  • Light is on, but trying to determine SEVERITY / range of expressivity
  • Patient has mutation, but there is a range of severity levels
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3
Q

Pleitropy

A

gene that has multiple effects within the body

  • How broad/how many different areas are effected
  • Polysystemic or Monosystemic
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4
Q

Mendel’s 2 laws are…

A
  • Mendel’s Law of Segregation: Alleles segregate (at meiosis) into the gametes
  • Mendel’s Second Law of Independent Assortment: the segregation of each pair of alleles is independent
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5
Q

3 threats to mendelian inheritance

A

penetrance
pleitropy
expressivity

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6
Q

The human genome is _________ and organized in a ______________

A

dynamic

non-random manner

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7
Q

There is an average of _______ SNPs every _________ bp between any two randomly chosen human genomes.

We are 99.9% identical but this still means we have _________ differences

A

1
1000 bp

3 million

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8
Q

The 4 types of variations that can occur between genomes are…

A

1) Insertion/Deletion Polymorphisms
2) Single Nucleotide Polymorphisms
3) Copy Number Variations
4) Other structural variations (inversion, duplications, translocations, large scale insertions/deletions)

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9
Q

Minisatellites are ____________ polymorphisms and consist of ___________. They are also known as _____________

A

insertion-deletion polymorphisms

consist of tandemly repeated 10-100 bp blocks of DNA

(aka Variable Number Tandem Repeats VNTR)

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10
Q

Microsatellites are _____________ polymorphisms and consist of __________. They are also known as ___________ and a common example is ____________

A

insertion-deletion polymorphism

di-, tri-, tetra- nucleotide repeats

AKA Short Tandem Repeat Polymorphisms (STRP)

EX) CAG repeats - abnormal CAG repeats in Huntington’s disease dictate if individual gets disease or not

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11
Q

SNPs can be detected by _________, and are used in _________ because they are so widely distributed

A

PCR

can be used in genetic fingerprinting

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12
Q

Copy Number Variations can vary in size from _______-______ and are the primary type of ________ variation.

A

200bp - 2 Mb

structural

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13
Q

CNV can be identified using ________

A

array comparative genomic hybridization

microarray, but with DNA

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14
Q

1q21 is a region on the genome that is _______ and is associated with _______ different diseases

A

unstable

12 different diseases

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15
Q

1q21

A
  • contains duff 12-20, highly variable protein coding region
  • humans have most copies
  • farther you get from humans the less copies
  • thought to be involved in human brain evolution
  • more instability in 1q21 = increase duff 1220 copy number –> increase in brain size
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16
Q

1q21 deletion –>

1q21 duplication –>

A

deletion –> schizophrenia, microcephaly

duplication –> autism, macrocephaly

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17
Q

G-C rich regions make up ____% of the genome, and A-T rich regions make up ____%

A 
GT = 38%
AT = 54%
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18
Q

GC and AT rich regions are used in finding _________

A

chromosomal banding patterns

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19
Q

Genome sequencing is focused on _____ regions with > ______ sequence gaps still remaining, and there is no completely sequenced and assembled human genome.

A

euchromatic, >200

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20
Q

Genome Composition:

1) _____ = translated (protein coding)
2) 20-25% = __________
3) ______% = “single copy” sequences
4) 40-50% = _________

A

1) 1.5% is translated (protein coding)
2) 20-25% is represented by genes (exons, introns, flanking sequences involved in regulating gene expression)
3) 50% “single copy” sequences
4) 40-50% classes of “repetitive DNA”

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21
Q

NextGen sequencing relies on ______ sequences, therefore _________ regions are typically unexamined such as _______

A

short read

complex, highly duplicated regions

such as 1q21

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22
Q

Missing Heritability

A

defined as the fact that single genetic variations cannot account for much of the heritability of diseases, behaviors, and other phenotypes.

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23
Q

Explain the relationship between gene duplication and evolution and problems with this

A
  • CNV involved in rapid, recent evolutionary change
  • link between evolutionarily adaptive copy number increases and increase in human disease
  • one gene copy carries out critical function, the other is free to vary
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24
Q

CNV regions are often enriched for _________, __________, and __________

A

human specific gene duplication
genome sequence gaps
recurrent human diseases

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25
Q

Gene families

A
  • composed of genes with high sequence similarity that may carry out similar but distinct functions
  • Arise through gene duplication
  • play major role in evolutionary change
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26
Q

____% of the genome is comprised of segmental duplications

A

5

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27
Q

Tandem Repeats (aka satellite DNAs) are used for _________ and some are found as part of ___________ on long arms of Chromosome 1, 9, 16, and Y

A

cytogenetic banding

human-specific heterchromatin

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28
Q

a-satellite repeats are _______ bp repeat units found _______. They are important for ________ and ________.

A

171

found near centromeric regions of all human chromosomes

important for chromosome segregation in mitosis and meiosis

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29
Q

Dispersed Repetitive Elements include _____ and _______ families. These can be responsible for _________

A

Alu
L1
responsible for aberrant recombination events between different copies of dispersed repeats (–> disease)

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30
Q

Alu Family, aka _________. Comprised of _____ bp, with ________ copies in the genome

A

SINE (short interspearsed repeat elements)

300 bp, 500,000 copies

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31
Q

L1 Family, aka _________. Comprised of _____ kb, with ________ copies in the genome

A

LINE (long interspersed repeat elements)

6kb, 100,000 copies

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32
Q

Retrotransposition may cause _________ of genes, and is due to what process?

A

insertional activation

mRNA –> cDNA (introns all gone) –> cDNA reinserted into genome

-can be innocuous or detrimental

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33
Q

There are ____ (#) of cross-over events of homologous chromosomes, and each cross-over contains a physical link between homologs called a ________

A

2-3

chiasma

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34
Q

Genetic variability among offspring is due to ________ and _________

A

Recombination/Crossing-over and Independent assortment

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35
Q

Independent assortment

A

Chromosomes can align in many different ways before being pulled apart (2^23 possible combinations)

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36
Q

In Prophase I of meiosis, ______ and _______ occur, such that homologous chromosomes are brought into alignment along the entire length of the chromosome and swap parts. These ______ are held together in _________.

A

synapsis and recombination

bivalents, held together in syntaptonemal complex

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37
Q

In metaphase I chromosomes undergo _________ when they line up at the metaphase plate

A

independent assortment

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38
Q

Homologous chromosomes separate in _________, and this process can result in ________

A

anaphase I

disjunction

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39
Q

At the end of meiosis I you go from _______ to __________

A

1 4n cell –> 2 2n cells

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40
Q

Sister chromatids separate in ________

A

anaphase II

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41
Q

At the end of meiosis II you create ________

A

4 haploid cells that are all genetically different

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42
Q

Nondisjunction in meiosis I =

A

100% abnormal gametes
2 cells = N+1
2 cells = N-1

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43
Q

Nondisjunction in meiosis II =

A

50% abnormal gametes
2 cells = N
1 cell = N+1
1 cell = N-1

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44
Q

Two possible mechanisms of nondisjunction

A

chiasmata positioning

freqeuncy of cross-over events

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45
Q

Chiasmata positioning results in nondisjunction because

A

cross over event occurs too near or too far from the centromere

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46
Q

Metacentric

A

centromere is located in the middle of the chromosome, such that the two chromosome arms are approximately equal in length.

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47
Q

Submetacentric

A

centromere is slightly removed from the center.

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48
Q

Acrocentric

A
  • centromere is near one end of the chromosome.

- everything on short arm is repetitive satellite and ribosomal DNA

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49
Q

_____ and ______ are dyes used in banding pattern staining to allow unequivocal identification of each chromosome

A

Giemsa and DAPI

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50
Q

Polyploidy

A

“many-ploidy” having a chromosome number that is more than double the basic or haploid number – 69, etc.

  • Triploid (3 sets) – 69
  • Tetraploid (4 sets) – 92
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51
Q

Aneuploidy

A

abnormal number of chromosomes

EX) Monosomy, trisomy

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52
Q

Mosaicism

A

presence of at least two genetically different cells in a tissue that is derived from a single zygote

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53
Q

Maternal age effect: Two-Hit Theory

A

1) More risk of non-disjunction because of diminished recombination due to lack of chiasma or mislocalization
2) Diminished ability of oocytes to successfully complete chromosome segregation in the presence of unfavorable recombination events

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54
Q

Maternal Age effect: Cohesion Complex Theory

A
  • Degradation of cohesion complexes established during fetal development between sister chromatids and homologs with age because of extended meiosis I
  • -> Terminalization (premature separation of homologs/sister chromatids –> aneuplodiy)
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55
Q

Balanced Structural Rearrangments

A
  • all genomic material is present, even though it is arranged differently
  • No loss or gain of genetic material
  • No phenotypic effect for heterozygote carrier
  • EXCEPTION: breakpoint in a gene, disrupting function
  • Can increase risk of producing abnormal gametes, risk to subsequent generations
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56
Q

3 examples of balanced structural rearrangments

A

1) Robertsonian Translocations
2) Inversions
3) Reciprocal translocations

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57
Q

Reciprocal translocations results in ________ formation when chromosomes of a carrier pair in meiosis, leading to either _______ or _______ segregation

A

quadrivalent formation

adjacent
alternate

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58
Q

Reciprocal translocation

A
  • reciprocal exchange of broken segments between non-homologous chromosomes
  • balanced structural rearrangement
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59
Q

When adjacent segregation of quadrivalents occurs this leads to the formation of __________

A

100% unbalanced gametes

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60
Q

When alternate segregation of quadrivalents occurs this leads to the formation of __________

A

1/2 normal gametes, 1/2 balanced reciprocal translocation gametes

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61
Q

Robertsonian translocation

A
  • Most common structural chromosomal rearrangement
  • Fusion of two acrocentric chromosomes → loss of both short arms (NOT deleterious, only satellite DNA)

→ reduction of chromosome number, but still considered balanced

-Normal phenotype in carrier, but can lead to unbalanced karyotypes in offspring (monosomies and trisomies)

62
Q

Two types of inversions

A

pericentric

paracentric

63
Q

Inversions

A
  • chromosome undergoes two double strand breaks of the DNA backbone, and the intervening sequence is inverted prior to the rejoining of the broken ends
  • formation of loop when homologous chromosomes are paired in recombination
  • can increase risk of abnormal gametes
64
Q

Pericentric Inversions

A
  • Include the centromere
  • Can result in gametes with duplication and deficiency of chromosome segments

-½ balanced, ½ unbalanced

65
Q

Peracentric Inversions

A
  • excludes centromere
  • can result in acentric or dicentric chromosomes after crossing over (unstable)

-1/2 balanced, 1/2 inviable

66
Q

Unbalanced Structural Rearrangements

A

abnormal chromosomal content, deletion or duplication in multiple genes

67
Q

Duplication results in gametes with _________ and deletion results in gametes with _________ (after fertilization with a normal gamete)

A

duplication –> partial trisomy

deletion –> partial monosomy

68
Q

Del (22)(q11.2) results in ________ and _______ syndromes due to a deletion of 3 Mb within 22q11.2 in one cope of chromosome 22. Symptoms include _______, ________, _________, _________

A
  • DiGeorge Syndrome, Vel-Cardio-Facial Syndrome

- Results in: heart defects, craniofacial anomalies, intellectual disability, and immunodeficiency

69
Q

DiGeorge Syndrome and Vel-Cardio-Facial Syndrome are a result of ___________

A

Del(22)(q11.2)

-deletion of approximately 3 Mb within 22q11.2 in one copy of chromosome 22

70
Q

Epigenetics

A

mitotically and meiotically heritable variations in gene expression not caused by changes in DNA sequence

EX) reversible, post-translational modifications of histones and DNA methylation

71
Q

DNA methylation of CpG islands results in ______, but some DNA methylation can result in __________

A

recruitment of silencing complexes, and silencing of gene expression

gene expression activation

72
Q

Genetic imprinting is _________ and is present in ___% of genes in the human genome

A

sex dependent epigenetic modulation of regulatory regions such as promoter sequences

10%

73
Q

DNA methylation of genetically imprinted genes have 3 main qualities…

A

1) established in the gamete
2) stably maintained in somatic cells after fertilization
3) reversible

74
Q

Imprinted DNA methylation is maintained in somatic cells by ________ when DNA is replicated

A

maintenance methyltransferases

75
Q

Imprinted DNA methylation is reversible because _________

A

it can be reset during gametogenesis to transfer the appropriate sex-specific imprint to progeny (based on their sex)

76
Q

Uniparental Disomy is _____________ and often results due to __________

A

the presence of two chromosomes only inherited from one parent

trisomy rescue

77
Q

Types of FISH probes include ________, _________ and __________

A

Centromere, Locus Specific, and Dual Fusion

78
Q

FISH probes use _________ which hybridize to cells and can identify _______ by looking for ________

A

fluorescently labeled specific DNA probes (no more than 200kb)

-can identify translocations by looking for fusion signals

79
Q

Centromere FISH probe is used for ________

EX) ______

A

enumeration

EX) ALL panel

80
Q

Locus Specific FISH probe is used for _________

EX) ______

A

identifying deletions/duplications

EX) p53

81
Q

Dual Fusion FISH probe is used for __________

EX) ______ and _______

A

identifying translocations

EX) BCR-ABL and PML-RARa

82
Q

Chromosomal microarray (CMA) can detect _______ but not ________, and has limited ability to detect _________

A

genomic deletions and duplications

NOT translocations

mosaicism

83
Q

Lab test diagnosis protocal includes these 3 steps:

A

1) Chromosomal Microarray (CMA)
- If duplication/deletion detected → consult Database of Genomic Variants (DGV) to see if it is a known disease region

2) Parental FISH studies – determine if finding is normal, rare, or familial
- Deletion/Duplication found on parent → further FISH testing of other family members

3) No deletion/duplication found, and no DGV hits, then do further data-base mining

84
Q

Pharmacogenetics

A
  • Variable response to individual genes
  • The study of differences in drug response due to allelic variation in genes affecting drug metabolism, efficacy, and toxicity
85
Q

Pharmacogenomics

A
  • variable response due to MULTIPLE LOCI across the genome

- Concerned with assessment of common genetic variants in the aggregate for their impact on the outcome of drug therapy

86
Q

Pharmacokinetics

A
  • absorption, distribution, metabolism, and excretion of drugs
  • whether, or how much drug reaches its target
87
Q

Drug Metabolism Steps (2)

A

Phase 1: polar group added to compound –> makes more soluble (usually hydroxylation)

Phase 2: add sugar/acetyl group to detoxify drug –> easier to excrete

88
Q

Pharmacodymanics

A
  • relationship between drug concentration at site of action and the observed biological effects
  • what happens when drug successfully reaches target
89
Q

CYP450 gene family (50+ types): most function to _________, and 90% are active in ___________.

A

inactivate drugs

phase I metabolism of common drugs

90
Q

______% of Codeine is inactivated by ______ and _____% of codeine is activated by _________

A

80% inactivated by CYP3A4

10% activated by CYP2D6

91
Q

grapefruit juice acts to _______ CYP3A activity. Therefore, when grapefruit juice is combined with Felodipine (treats HTN) the result is _______________

A

inhibit

significant hypotension - low metabolism of drug because CYP3A is inactivated, thus over-activation of drug effects

92
Q

_______ is used to treat fungal infections and acts to temporarily inhibit _______ metabolism of cyclosporine

A

Ketoconazole

CYP3A

93
Q

When Ketocanazole is combined with ________, you must _________ or risk neprotoxicity because ________ is inhibited

A

cyclosporine
must decrease cyclosporine dose
CYP3A metabolism of cyclosprine

94
Q

________ is a TB prophylaxis drug that acts to _______ thus ___________. Therefore, you must ________

A

Rifampin

CYP3A inducer thus increasing metabolism of cyclosporine.

Must increase dose of cyclosporin

95
Q

CYP2D6

A

needed to activate codeine into morphine

96
Q

VKORC1 = ? and is metabolized by _______

A

Warfarin (narrow therapeutic window)

CYP2C9

97
Q

NAT = is a __________ enzyme whose rate is determined by ________. _______ (drug) is a TB prophylactic drug metabolized by NAT.

If drug is metabolized to fast –> ?

If drug is not metabolized enough –> ?

A

N-Acetyltransferase enzyme (important in phase II metabolism), reate determined by genetic polymorphisms

Isoniazid

If drug is metabolized to fast –> not effective in preventing TB

If drug is not metabolized enough –> liver damage/failure

98
Q

TPMT (Thiopurine-S-methyltransferase) is used to treat ______

If drug is metabolized to fast –> ?
If drug is not metabolized enough –> ?

A

treats childhood leukemia

If drug is metabolized to fast –> not effective in treating leukemia

If drug is not metabolized enough –> immunosuppressant can cause death from bone marrow failure

99
Q

G6PD deficiency

A
  • X-linked Recessive
  • most common human enzyme deficiency
  • Increases malarial resistance (common among blacks)
  • subject to hemolytic anemia after certain drug exposures
100
Q

Population genetics

A

the study of allele frequencies and changes in allele frequencies in populations

101
Q

Polymorphism

A

genetic variant (mutation) which is common (>1%) in the populations

102
Q

Mutation rate (u)

A

Frequency of new mutations at a given genetic locus

103
Q

Calculating mutation rate:

Direct method
Indirect Method

A

Direct method:
u = number of cases without family history/ (total population x 2 allels)

Indirect Method: used when f=0
I=2u

104
Q

Fitness (f)

If F=1 ?
If F=0 ?

A

o Probability of transmitting one’s genes to the next generation

F=1 (same as normal population)

F=0 (gene(s) not passed on)

105
Q

Coefficient of Selection (S)

A

S = 1 - f

106
Q

Hardy-Weinberg Assumptions

A

1) Population is large and matings are random
2) Allele frequencies remain constant over time because:
- No appreciable rate of mutation
- All genotypes are equally fit (equal chance to pass alleles to next generation)
- No significant immigration/emigration of individuals with different allele frequencies

107
Q

Carrier frequency =

A

2pq

when q is more rare than 1/10,000 can use 2q as an estimate for carrier frequency

108
Q

p=?

q= ?

A 
p = frequency of common allele
q = rare allele
109
Q

3 Types of Down Syndrome

A
  • Trisomy 21 (95% of the time) (maternal nondisjunction in meiosis I usually)
  • Unbalanced Translocation (3-4%) between chr21 and another acrocentric chromosome
  • Mosaic Trisomy 21 (1-2%) – more mild phenotype
110
Q

Down Syndrome Physical Features

A
  • Flat faces
  • prominent epicanthal folds
  • Upslanting palpebral fissures
  • Single palmar crease
  • small ears
  • gap between 1st 2 toes
  • Large-appearing tongue
  • Low muscle tone
  • Increased joint mobility
111
Q

Down Syndrome Medical Problems

A 
Duodenal atresia
Hirschsprung disease (constipation)
Congenital heart disease (atrial septal defect)
Early onset Alzheimer's
Increased ALL risk

Other:

  • Eye: myopia (near-sightedness), lazy eye, blocked tear ducts, nystagmus, cataracts
  • ENT: ear infections, deafness, enlarged tonsils/adenoids
  • Endocrine: diabetes, thyroid, reduced fertility
  • Ortho: hips, joint subluxation, atlantoaxial subluxation
112
Q

Down Syndrome Developmental and Behavior Phenotypes (6)

A
  • Hypotonia – gross motor development effects
  • Spectrum of intellectual disability (Mild-moderate usually)
  • Speech problems
  • Seizures
  • Alzheimer’s
  • Autism
113
Q

Trisomy 18 (Edwards Syndrome)

Clinical Features (4)

A
  • Small for gestational age
  • Small jaw
  • low-set ears
  • Clenched fingers
  • Rocker-bottom feet

-Very high lethality within 1 year

114
Q

Trisomy 13 (Patau Syndrome)

Clinical Features

A
  • Characteristic faces
  • Severe intellectual disabilities
  • facial clefts
  • polydactyly
  • renal anomolies
115
Q

45XO is ___________

A

Turner Syndrome

116
Q

47XXY is ___________

A

Kleinefelter Syndrome

117
Q

Turner Syndrome clinical features

A
  • short stature
  • webbed neck
  • broad chest
  • low set ears
  • cubitus valgus
  • inner canthal folds
  • blue sclera
  • NORMAL INTELLIGENCE
  • hormone dysfunction
  • gonadal dysgenesis
  • coarctation of the aorta
  • Prolonged QTc
  • scoliosis
118
Q

Turner Syndrome prevalence

A

1/2500 newborn girls
99% do not survive to term
mosaic karyotypes thought to contribute to survival

119
Q

Klinefelter Syndrome prevelance

A

47XXY
1/500-1/1000 newborn boys
can occur due to maternal or paternal meiosis I

120
Q

Klinefelter Syndrome Clinical Features

A
  • Tall stature
  • Hypogonadism (small testes)
  • gynecomastia
  • usually sterile
  • learning disabilities
  • delayed speech/language
121
Q

Prader-Willi Syndrome (PWS) can be caused 3 ways

A

1) 15q11-q13 deletion on paternal chromosome (70%)
2) Maternal uniparental disomy (20-30%)
3) Abonormalities in imprinting center (2.5%)

122
Q

PWS 15q11-q13 deletion can be caused by _______ and can be detected with ______ and ________

A

Caused by misalignment during homologous recombination of repeats flanking 15q11-q13

Detect with FISH and Microarray

123
Q

Maternal uniparental disomy is 2 copies of the ______ allele and can be detected with __________

A

maternal

detect with methylation testing

124
Q

PWS abnormalities in imprinting center results when fertilization occurs by _________ causing the cell to think there is maternal UPD

A

sperm with abnormally persistent female imprinting

125
Q

Detect abnormalities in imprinting center with ___________

A

methylation testing

126
Q

PWS physical features (4)

A

-Changes in facial features (almond shaped eyes)
-Undescended testicles (males)
-Severe feeding problems (require G-tube) until 2-4 years when they completely reverse (insatiable appetite)
→ Obesity (can treat with Growth Hormone)

127
Q

PWS medical problems

A
  • Ortho: Scoliosis common
  • Eyes: Nystagmus, strabismus
  • Resp: obstructive sleep apnea
128
Q

PWS developmental and behavioral problems

A
  • mild-moderate cognitive disabilities

- behavioral issues are common

129
Q

Angelman Syndrome can be caused 4 ways

A

1) 15q11-q13 deltion on maternal chromosome (70%)
2) Paternal uniparental disomy (7%)
3) Abnormalities in imprinting center (abnormally persistent male imprint) (3%)
4) Genetic mutation in UBE3A (10%)

130
Q

UBE3A is usually only expressed from the ______ allele, so mutation can cause _______ 10% of the time

A

maternal

Angelman Syndrome

131
Q

AS phenotype (6)

A
  • mildly dysmorphic facial features
  • hypotonia
  • spasticity in older patients
  • Intellectual Disability
  • seizures
  • autism
132
Q

IDIC 15 (15q11-q13) is a _________ derived abnormality that causes ________. These patients are NOT ______ but often suffer from _______ and ________

A

maternally
causes autism
NOT dysmorphic

suffer seizures, and are hypotonic

133
Q

Maternal 15q Interstitial Duplication only results in phenotypic effects if it is __________

A

maternally inherited

134
Q

Maternal 15q Interstitial Duplication results in ______, with _____ and ______ common,. These patients are NOT _________

A

autism
seizures, hypotonia common

NOT dysmorphic

135
Q

Chronic Myeloid Leukemia (CML) results from a ________ translocation involving chromosomes _____ and _____

A

BCR-ABL, chr 9 and 22

136
Q

CML can be treated by ________

A

Gleevec

137
Q

Gleevec is a _______ and acts to _________

A
  • tyrosine kinase inhibitor
  • targets novel protein (tyrosine kinase signaling molecule) generated by translocation
  • -> Gleevec binds ATP binding site, inhibiting action
138
Q

Acute Pro-Myeloid Leukemia (APML) results from a _______ balanced translocation involving chromosome _____ and _____

A

RERalpha and PML translocation

chr 15 and 17

139
Q

RERa and PML translocation results in a _________ that acts to _________

A
  • novel transcription factor

- bind to promoter elements in DNA, inhibiting transcription downstream

140
Q

Acute Pro-Myeloid Leukemia is treated with ________ which acts to _________

A

Vitamin A

-bind novel protein TF–> changes protein conformation –> allows transcription to continue when coactivators bind

141
Q

Childhood B-cell Leukemia:

Hypodiploid = ?
Hyperdiploid = ?
A

Hypodiploid = 38 chromosomes in cancer cells (poor prognosis, needs aggressive treatment)

Hyperdiploid = 55 chromosomes in cancer cells (more favorable diagnosis)

142
Q

47XYY = ?

A

Jacobs Syndrome

143
Q

Jacobs syndrome clinical features and prevalence

A

-Learning disabilities
-Speech delays
-developmental delays
-emotional/behavioral difficulties
autism
-tall stature

1/1000 newborn boys

144
Q

47XXX = ?

A

Triple X syndrome

145
Q

Triple X syndrome clinical features/risks and prevalence

A
  • Tall stature
  • risk of learning disabilities, delayed speech/motor, seizures, kidney abnormalities

1/1000 newborn girls

146
Q

Androgen Insensitivity Syndrome

A

46XY

  • x-linked gene
  • Androgen Receptor mutation
  • Androgens (testosterone) is present, but body does not recognize/respond to it
147
Q

5-alpha reductase deficiency

A

46XY
-Body can’t convert testosterone to dihydrotestosterone

-Phenotype: undervirilized male with increased virilization at the time of puberty

148
Q

SRY disorders:

SRY deletion = ?
Presence of SRY in 46XX = ?
Mutations in SRY = ?

A

Deletion/Absence of SRY → phenotypically normal female

Presence of SRY in 46XX → phenotypically normal male

Mutations in SRY → decreased/absent AMH, under-virilization of a male

149
Q

Denys-Drash and Frasier Syndrome (genotype = ?) results from a mutation in ________ which is a _________. Can result in ________, _________, and ______

A

46XY
WT1 gene, an SRY transcription factor

Can result in: kidney disease, increased tumor risk, and sex reversal

150
Q

Congenital Adrenal Hyperplasia (genotype = ?) and results in ________, ________, and _________

A

46XY
ambiguous genitalia
21-hydroxylase deficiency
risk of salt wasting

151
Q

Who am I?

  • short stature
  • webbed neck
  • broad chest
  • low set ears
  • cubitus valgus
  • inner canthal folds
  • blue sclera
  • NORMAL INTELLIGENCE
  • hormone dysfunction
  • gonadal dysgenesis
  • coarctation of the aorta
  • Prolonged QTc
  • scoliosis
A

Turner Syndrom XO

M2M Unit 2 (2 decks)

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