Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Human reproduction and fertility > imprinting disorders > Flashcards

imprinting disorders Flashcards

1
Q

why are gynogenetic or androgenetic diploids inviable?

A

due to genomic imprinting

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

what side is IGF-11 controlled by?

A

paternal side- is maternally imprinted

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

what side is IGFIIR controlled by?

A

maternal side

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

what phenotype to mice with a IGF11 mutation transmitted down the paternal line have?

A

growth defects

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

what is maternal imprinting?

A

allele inherited from the mother is transcriptionally silent, phenotype is governed by paternal side

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

what two situations can lead to imprinting diseases?

A

both copies of the gene are silenced or mutations in the expressed alllele

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

what causes Beckwith-Weirdemann syndrome?

A

maternal igf2 allele on chromosome 11 is not silenced due to imprinting defect in IC1. hypomethylation at potassium channel DMR region

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

what are the symptoms of BWS?

A

pediatric overgrowth, predisposition to tumours

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

inheritance pattern of BWS?

A

paternally inherited

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

symptoms of anglemans?

A

development difficencies, sleep disorders, seizures

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

inheritance pattern of anglemans?

A

maternally inherited, paternally imprinted chromosome 15

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

genetic causes of anglemans

A

deletions of PW region, point mutations in maternal UBE3a or paternal UPD

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

symptoms of prader willi

A

obesity, behaviour and cognitive problems

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

inheritance pattern of PW

A

paternally inheirted, maternally imprinted chromosome 15

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

genetic causes of PW

A

70% PW region deletion, 25% maternal UPD, mutations in ICR or translocations that separate ICR from PW region

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

symptoms of silver russel

A

pre and postnatal growth retardation, small triangular face, sweaty head and cardiac defects

17
Q

genetic causes of silver russel

A

maternal UPD of chromosome 7, maternal duplication of 11p15, hypomethylation of telomeric 11p15 IC- supresses IGF2 expression

18
Q

what is H3K14ac a docking site for

A

bromo-domain proteins

19
Q

what genes are associated with birth size?

A

paternally expressed IGF2 and maternally expressed H19

20
Q

why does epigenetic reprogramming take place in PGCs

A

resets imprinted genes for sex-specific reacquision, erases parental acquired epigenetic memories, facilitates gametogenesis, maintains silenicing of transposbale elements, reduces germline mutation rate

21
Q

why does reprogramming take place in pre-implantation embryo

A

resets zygotic marks for naive pluripotency, maternal v paternal genome wars- allows more contribution from females

22
Q

how are PGC epigenentic memories erased?

A

global DNA demethylation, genomic imprint erasure, x chromsoomes reactivation and reorganisation of histones

23
Q

after pGC development what happens to XY and XX germ cells?

A

XY enter mitotic arrest, XX enter meiosis

24
Q

when does remethylation occur in males and females?

A

in SSCs in males and after birth in growing oocytes in females

25
Q

what happens to ICRs in PGC resetting?

A

imprints erased and resestabilished in sex specific manner later in development

26
Q

how are embyros reset in females?

A

through replication dependent passive mechanisms- PRDMI and PRDM14 repress DMNT3a and b and UHRF1. UHRF1 normally activates DNMT1

27
Q

how are embryos reset in males? a

A

active mechanisms- 5mC converted to 5hmC by TETs then removed in passive way or by base excision repair

28
Q

how may imprints escape erasure during embryo restting?

A

these regions have higher numberrr KAP1 binding regions and may recruit DNMT1

29
Q

why did dolly die young?

A

no restting of epigenetic marks, would not be pluripotent, demethylated in a non-speicifc and delayed way.

30
Q

steps in artificial gamete production

A

1perform SCNT on somatic cell and induce embyro development in vitro
2. extract ESC from blastocyst
3 induce gametogenesis in vitro
4 use gamete to fertilise partners egg/sperm
5 develop embryo and implant into mother

31
Q

what are man made mouse eggs made from?

A

in vitro system of generating a mouse oocyte from fibroblast derived pluripotent stem cells

32
Q

how are bimaternal mice made?

A

oocyte activated, isolate parthenogenetic haploid ESCs, demethylate cells in media- loss of methylation non-specifc, then delete paternally imprinted regions- found that deleting 3 regions made basically normal mice, then implant haploid ESC into mature oocyte

33
Q

how are bipaternal mice made?

A

mature oocyte enucleated and fertilised with sperm, androgenetic haploid ESCs isolated, demethylate in media, deleting 6 maternally imprinted regions still resullted in death, then coinject haploid ESC and sperm into enucleated oocyte.

Human reproduction and fertility (9 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions