Genetics

Question 1

how many base pairs are there in the human genome?

Answer 1

3,000,000,000

Question 2

how many genes make a human?

Answer 2

30,000

Question 3

we know there are 10,000,000 possible places for a polymorphism

how many polymorphisms do you find on average in a person?

Answer 3

3,000,000

Question 4

what technique allows you to look for sub-microscopic deletions or duplications of chromosome material across the whole human genome?

Answer 4

Chromosome MicroarrayArray Genomic Hybridisation (aCGH)

Question 5

half as much DNA = ________

50% more DNA = ___________

Answer 5

half as much DNA = DELETION

50% more DNA = DUPLICATION

Question 6

aCGH only detects __________ chromosome rearrangements

Answer 6

aCGH only detects UNBALANCED chromosome rearrangements

Question 7

a deletion on chromosome 22q indicates what?

Answer 7

Digeorge Syndrome

Question 8

Delivered at 38 weeks gestation by SVD
Apgar scores 6/1, 8/5,9/10 minutes
Skin to skin care with mum and attempted breast feeding over first 16 hours
Asked to see by midwife at 16 hours of age because not feeding and floppy
Male infant with Birth Weight 2.45 kg
OFC 32 cms
Offered breast feeds every 3 hourly but not fixed and weak suck only
Temperature 36.8 degrees celsius

what is the first genetic test?

Answer 8

Array Comparative Genomic Hybridisation

Question 9

what is considered normal?

Answer 9

the commonest form of gene sequence

Question 10

name the following mutations:

(a) the cat sat on the mat
(b) the cat
(c) the car sat on the mat
(d) the cat spa to nth ema t
(e) the cas ato nt hem at
(f) the cat on the mat
(g) the cat cat sat on the mat

Answer 10

(a) the cat sat on the mat - WILD TYPE
(b) the cat - STOP
(c) the car sat on the mat - MISSENSE

(d) the cat spa to nth ema t - INSERTION
(e) the cas ato nt hem at -
DELETION (OUT OF FRAME)

(f) the cat on the mat - DELETION (IN FRAME)
(g) the cat cat sat on the mat - TRIPLET EXPANSION

Question 11

speech delay
cleft palate
unusual eyes and eyebrows
tendency to drool
short 2nd phalanges of 5th finger

diagnosis?

Answer 11

Kabuki makeup syndrome

Question 12

where is the mutation in someone with Kabuki makeup syndrome?

Answer 12

MLL2

Question 13

name the biggest determinant of de-novo mutations in children

Answer 13

paternal age

Question 14

how do we treat tuberous sclerosis?

Answer 14

rapamycin that targets mTor signalling

Question 15

infant with out-turned bottom lip, cardio problems and altered intellect

diagnosis?

Answer 15

william syndrome