Genetic and pathobio of disease

Question 1

application of genetic knowledge (3)

Answer 1

1. confirmation of exact diagnosis and counselling
2. cancer prognosis and treatment
3. risk assessment in other family members

Question 2

why are genetic important in peds

Answer 2

1. 2-3% born with congenital anomaly

2. leading cause of death in neonatal period

Question 3

importance of genetics in adults

Answer 3

5% of under 25 dev. illness with genetic component

- 67% chance if consider CV and cancer

Question 4

what is spectrum of genetic influence

Answer 4

entirely genetic to entirely environmental

Question 5

when do different disease types show up

Answer 5

chromosomal - before birth
single gene - childhood
multifactorial - later in life

Question 6

what are chromosomes

Answer 6

physically separate strand of DNA

Question 7

what are human chromosomes

Answer 7

23 + a sex

Question 8

def. karytype

Answer 8

lab technique that produces picture of chromosomes

Question 9

def. aneuploidy

Answer 9

abnormal number of chromos

Question 10

2 types of aneuploidy

Answer 10

1. consitiutioknsal - every cell

2. somatic - only in some cells - cancer

Question 11

what is chromosome structure

Answer 11

short (p) arm and long (q) arm separated by centromere

Question 12

what are other chromo imbalances

Answer 12

micro deletions and duplications - can’t see on karyotype

Question 13

how to see micro

Answer 13

flourescence in situ (FISH)

Question 14

what is FISH

Answer 14

use a probe with are looking for to flouresce that region

Question 15

what is chromo microarray

Answer 15

like doing hundreds of FISH at once

Question 16

def. proteome

Answer 16

constellation of all proteins in a cell

Question 17

what is average gene size

Answer 17

3000 nucleotides

Question 18

what is actual coded portion of gene

Answer 18

exons

Question 19

what is central dogma

Answer 19

DNA>RNA>protein

Question 20

3 ways a single gene defect can be inherited

Answer 20

1. autosomal dominant
2. recessive
3. x-linked - affects male preferentially

Question 21

look at the genograms

Answer 21

do it

Question 22

def. mutation

Answer 22

1. perm. change in the DNA sequence of a gene

- may be single nucleotide to large sequence

Question 23

2 types of mutaitons

Answer 23

1. germline - from parents

2. somatic - aquired

Question 24

3 ways mutations can happen

Answer 24

1. point mutations
2. insertion mutations
3. deletions

Question 25

poss. results of point

Answer 25

silent, missense, nonsense (stop)

Question 26

def. polymorphism

Answer 26

genetic changes that are common in the pop. (>1%)

Question 27

what is common form of polymorphism

Answer 27

SNP - single nucleotides

Question 28

def. locus

Answer 28

specific location on a chromosome - usually refers to a specific gene

Question 29

def. allele

Answer 29

alternate forms of a gene

Question 30

how do mutations lead to disease

Answer 30

usually with gain or loss of function

Question 31

what is loss of function

Answer 31

• most genetic disease
• proteins have less or no function
• most reccesive mutations

Question 32

what is gain of function

Answer 32

• proteins with new or abnormal function

- typically autosomal dominant

Question 33

example of loss of function and gain of function

Answer 33

loss - CF - loss of CFTR transporter - mucous

gain - achondroplasia - fibroblast growth facotr gene - increased chondorcyte inhibition

Question 34

4 approaches to pathobiol of disease and genetics

Answer 34

1. multifactorial or genetic
2. chromosomal
3. molecular
4. other