Genetics

Question 1

boy genotype

Answer 1

XY

Question 2

girl genotype

Answer 2

XX

Question 3

histone proteins

Answer 3

DNA is wrapped around histone proteins to form chromosones

Question 4

mitosis

Answer 4

1 diploid parent cell divides into 2 identical daughter cells (not 100% identical due to mutations)

Question 5

meiosis

Answer 5

1 diploid cell becomes 4 haploid daughter cells

Question 6

process of meiosis

Answer 6

chromosomes duplicate
chromosomes line up and cross over
one chromosome to each daughter

Question 7

what increases variation of meiosis

Answer 7

crossing over

Question 8

polymorphism

Answer 8

variation in the human genome that is not directly disease causing

Any variation in the human genome that has a population frequency of greater than 1%

Question 9

mutation

Answer 9

a gene change

Question 10

when does mitosis occur

Answer 10

whenever more cells are needed

Question 11

acrocentric chromosome

Answer 11

centromere is close to the bottom or top of chromosome

Question 12

unbalanced chromosomal rearrangement

Answer 12

extra or missing chromosomal material

Question 13

balanced chromosomal rearrangement

Answer 13

All the chromosomal material is present

Question 14

translocation

Answer 14

rearrangement of chromosomes

Question 15

Aneuploidy

Answer 15

whole extra or missing chromosomes

Question 16

robertsonian translocation

Answer 16

two acrocentric chromosomes stuck end to end

Question 17

trisomy

Answer 17

chromosomal disorder with an extra chromosome

Question 18

down syndrome

Answer 18

extra 21 chromosome

Question 19

turner syndrome

Answer 19

only one x chromosome

Question 20

triple x syndrome

Answer 20

women with 3 x chromosomes in every cell

Question 21

Klinefelter syndrome

Answer 21

males with at least 2 chromosomes and 1 y chromosome

Question 22

monosomy

Answer 22

missing chromosome from diploid set

Question 23

FISH

Answer 23

Fluorescence in situ hybridization

Question 24

what test would you use to examine whole genome?

Answer 24

aCGH
detects missing/duplicated material but many are neutral
first line

Question 25

what test would you use to examine specific chromosomes

Answer 25

quantitative PCR

Question 26

mocaism

Answer 26

different cells have a different genetic make up

Question 27

what do exons do?

Answer 27

code for proteins

Question 28

what do introns do?

Answer 28

- regulate genes - space out genes from promotors - provide a substrate for expanding the genome

Question 29

germ cells

Answer 29

sex cells

Question 30

germline mocaism

Answer 30

2 populations of sex cells in an individual

Question 31

somatic mociasm

Answer 31

2 populations of non sex cells in an individual

Question 32

cancer and mocaism

Answer 32

cancer is a disease of somatic mocaism caused by post zygotic mutations

Question 33

zygote

Answer 33

cell formed by the fertilisation of two gametes

Question 34

hallmarks of cancer

Answer 34

``` evade apoptosis sustained growth signalling insensitivity to anti growth signals tissue invasion and mets limitless replicative potential sustained angiogenesis ```

Question 35

angiogenesis

Answer 35

new blood vessel formation

Question 36

genes involved in cancer

Answer 36

oncogenes: signal cell growth tumour supressors: stop cell growth dna repair: repair damaged DNA drug metabolism: metabolise carcinogens

Question 37

driver mutations

Answer 37

mutations that drive carcingens

Question 38

passenger mutations

Answer 38

mutations that occur bc the tumour is unstable

Question 39

knudsons 2 hit hypothesis

Answer 39

cancers arrise from the accumulation of multiple dna mutations

Question 40

penetrance

Answer 40

the extent of which a gene is expressed in the phenotype of an individual measured by the proportion of carriers with the characteristic phenotype

Question 41

what gene is linked with breast cancer

Answer 41

BRCA1

Question 42

are cancers genetically stable or unstable?

Answer 42

unstable

Question 43

name of the condition in men with at least 2X chromosomes

Answer 43

kleifelter syndrome

Question 44

when 2 acrocecntric chromosomes join together

Answer 44

robertsonian translocation

Question 45

women with only oneX chromosomr

Answer 45

turner syndrome

Question 46

name of the condition with whole missing or extra chrmosomes

Answer 46

aneuploidy

Question 47

conditions with one chromosome

Answer 47

monosomy

Question 48

condition with 3 chromosomes

Answer 48

trisomy

Question 49

edwards syndrome

Answer 49

3rd copy of choromosone 18

Question 50

- 1st line chromosome test

Answer 50

microarray CGH | detects missing or duplicated chromosomes

Question 51

Autosomal Dominant

Answer 51

- Disease seen in all generations - 50% risk of affected child if parent affected - Disease severity variable - Males and females equally likely to be affected

Question 52

autosomal recessive

Answer 52

- 2 faulty copies of the gene required to cause disease - Often only one generation affected - 1 in 4 (25%) risk of an affected child if parents are carriers - I

Question 53

X linked

Answer 53

- Recessive - Y chromosome almost irrelevant - Haemophilia - If mother carrier, 50% chance daughter carrier, 50% chance male affected - No male-male transmission

Question 54

X inactivation

Answer 54

- A cell only requires one working copy of the X chromosome. In females, each cell has a random X chromosome inactivated