L12 -diagnosing gentic disease Flashcards Preview

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Flashcards in L12 -diagnosing gentic disease Deck (23):
1

why is chr study imp

chr abn cause infertility and recurrent miscarriage
>50% of spontaneous abortion inthe first trimester ar the result of chr abn

2

what is polyploidy

numerical abn
inc triploidy - extra of each chr

3

what cause triploidy

2 sperm one egg
diploid egg

4

consequence of triploidy

v rare go to term
norm spontaneous abort

5

what is aneuploidy

one or more ind chr extra/missing

6

what is monosomy and consequence

lack of a chr
lethal in autosome

7

what is trisomy and consequence

extra copy of a chr
lead to early miscarriage
chr 11/18/21 sruvive to term

8

what eg of a sex chr aneupolidy

klinefelter

9

eg of a autosome aneuploidy

down syndrome
70% abort naturally

10

eg of a disease caused by chr abn of del

prader willi syndrome
15q11 pat del (and not expr by mat)
7 gene del
foodseek behav /obesity

11

disease eg of chr abn of insertion

7q11.23 = dup of 28 genes
deep set eyes/long nose/speech dyspraxa

12

what is a ring chr

mut event removes both telomeres
repair by fuse ends together
ring chr 20 assoc with epilepsy

13

how commmon are chr tanslocations

1:500

14

what the adv of karyotpye

whole genome
gross abn detect
cells from various tissues can be used

15

disadv of karyotype

limited resolution >5mb
slow
relative £
skill to interpret
cant detect unbal rearr

16

describe karyotpe

look at gtg bind patterns

17

what the adv of FISH

detect small rearr
>0.5mb
high res
cheap
easy to interpret
can use mutiple probes
can study metaphase chr or interphase nuclei

18

what the disadv of FISH

have to know where to look

19

what disease FISH detect

Williams sybdrome
norm karyotpe
FISH shown 1.5mb del on 7q11.23

20

what the adv of aCGH

whole genome or any targeted chr
quantitative ata on dup and del
cheap
can get good res

21

disadv of aCGH

cant detect bal rearrrangements
no info on location of extra info

22

the mech used to validate findings of microarray

qPCR - res down to 100bp / cheap/quick
MLPA
tiled oligonuc microarray

23

how can a balced abn give ptype

pot unequal loss/gain of genes
breakpoints disrupt gene or sep from reg element