Exam 5 Exam Material

Question 1

Autosomal dominant

Answer 1

DD and Dd, Delayed onset, Huntington disease

Question 2

Autosomal recessive

Answer 2

Dd and Dd, Early onset, uniform symptoms

Question 3

X linked recessive

Answer 3

Xx and Xy, Only males effected usually, Hemophilia A an B

Question 4

Penetrance

Answer 4

Portion of people in population with mutated gene that shows traits

Question 5

Expressivity

Answer 5

How a gene presents itself, complete, moderate, minimal, no penetrance/expression

Question 6

Genetic variants

Answer 6

Pathogenic, Benign, Likely Pathogenic, Likely benign, Uncertain significance

Question 7

New de novo variants

Answer 7

Found in children not parents, in egg or sperm of parents but not in other cells, can lead to mosaicism

Question 8

Missense mutation

Answer 8

Change 1 nucleotide, amino acid to different amino acid, produce malfunctioning proteins

Question 9

Nonsense mutation

Answer 9

Single nucleotide change, change amino acid to stop codon, causes frame shift, multiple of 3 does not cause frame shift

Question 10

Three types of mutations that cause autosomal dominant disorders

Answer 10

Loss of function, Osteogenesis imperfecta, gain of function

Question 11

Loss of function

Answer 11

Loss of LDL-R
can’t remove LDL from body
Familial hypercholesterolemia

Question 12

Osteogenesis imperfecta

Answer 12

Defects in production of collagen
2 subunits alpha 1, 1 subunit alpha 2

Question 13

Gain of function

Answer 13

PCSK9 binds to LDL receptor
Directs it to lysosome

Question 14

Cystic fibrosis

Answer 14

Recessive disorder LOF, most common affecting Caucasians, affects fluid secretion in exocrine glands, respiratory lining, GI, and reproductive tracts

Question 15

Translocation

Answer 15

transfer part of a chromosome to another

Question 16

Isochromosome

Answer 16

Centromere divides horizontally instead of vertically

Question 17

Deletion

Answer 17

Loss of a portion

Question 18

Inversion

Answer 18

Two interstitial breaks the segment reunites but is flipped

Question 19

Ring chromosome

Answer 19

A variant of deletion after loss of segments from each end of the chromosome, the arms unite to form a ring

Question 20

Down syndrome

Answer 20

Trisomy 21, 3 copies, meiosis 1 nondysjunction, excess skin on back of neck, transverse palmar crease, folded ear

Question 21

Turner syndrome

Answer 21

Monosomy X, single X chromosome in females

Question 22

Triplet repeat mutations

Answer 22

Longer repeats cause disruption of gene function
40 neurodegeneration diseases, fragile X

Question 23

Mitochondrial mutations

Answer 23

Only inherited from mother, males can’t transmit to offspring, affected organs depend on oxidative phosphorylation (skeletal muscle, heart, brain)

Question 24

Cytogenetic disorders

Answer 24

In 1/200 infants, change in chromosome number or structure, autosomes or sex chromosomes, disorders from autosome number are more severe than single gene disorders

Question 25

Genetic imprinting

Answer 25

Some regions of DNA inactivated in copy received from mother or father

Question 26

Maternal imprinting

Answer 26

silencing of maternal allele

Question 27

Paternal imprinting

Answer 27

Transcriptional silencing of paternal allele

Question 28

Prader willi

Answer 28

Chromosome 15 deletion from father

Question 29

Angelman syndrome

Answer 29

chromosome 15 deletion from mother

Question 30

Neoplasia

Answer 30

Abnormal growth of cells and tissues characterized by dysregulated cell proliferation

Question 31

Difference between malignant and benign

Answer 31

Cancers are less differentiated, invasive, and metastatic

Question 32

Grading

Answer 32

estimate of aggressiveness level of malignancy based on differentiation and greater clinical value

Question 33

Three fundamental principles of carcinogenesis

Answer 33

Genetic changes lie at the heart of carcinogenesis, carcinogenesis is multistep, oncogenes and tumor suppressive genes are targets of this damage

Question 34

Oncogenes

Answer 34

genes that encode proteins that inhibit cancer

Question 35

Two hit hypothesis

Answer 35

Need a mutation in both genes to lose activity of tumor suppressor and to develop cancer

Question 36

Pediatric cancers

Answer 36

Tend to have single genetic events that are important at a specific developmental time

Question 37

Adult cancers

Answer 37

rarely have a single genetic mutation

Question 38

X ray and cosmic radiationcause

Answer 38

genetic lesions

Question 39

Six hallmarks of cancer cells

Answer 39

Self sufficiency in growth signals Insensitivity to anti-growth signals Tissue invasion and metastasis Limitless replicative potential Sustained angiogenesis Evading apoptosis

Question 40

G0/G1

Answer 40

Building blocks, duplicated contents but not chromosomes

Question 41

G1 checkpoint

Answer 41

Cell size, nutrients, dna damage, growth factors

Question 42

S

Answer 42

cell replicating DNA

Question 43

G2

Answer 43

cell assembles for chromosome segregation and cytokinesis double checks duplicated chromosomes

Question 44

M

Answer 44

mitosis, spindle assembly checkpoint

Question 45

Telomerase expression

Answer 45

Leads to cell immortalization, limitless replicative potential, telomeres at the end of chromosomes shorted with every division

Question 46

How tumor cells induce angiogenesis

Answer 46

Produce vascular endothelial growth factor

Question 47

How inflammation increases cancer risk

Answer 47

Results in persistent regenerative cell proliferation or hyperplasia and dna damage as a result of reactive oxygen and nitrogen species produced by immune cells

Question 48

PTEN

Answer 48

Phosphatase that reverses PI3K kinase phosphorylation

Question 49

NF1

Answer 49

Inhibits Ras

Question 50

BAX

Answer 50

pro-apoptotic regulators

Question 51

VEGF

Answer 51

promotes angiogenesis

Question 52

LMP1 and LMP2

Answer 52

In Epstein Barr virus, cell surface receptors that activate mitogenic signaling in B cells

Question 53

vFLIP

Answer 53

In Kaposi's herpesvirus, increases metastasis and angiogenesis

Question 54

MCPV

Answer 54

Merkel cell polyomavirus, requires infection then mutation of the large T antigen in elderly and immunocompromised

Question 55

HPV

Answer 55

Human papillomaviruses cause cervical cancer because E6 targets p53 and E7 targets Rb

Question 56

TAX

Answer 56

In HTLV-1, increases expression of genes that promote proliferation, DNA repair, and resistance to apoptosis

Question 57

Loss of APC

Answer 57

results in hyperproliferative colonic epithelium

Question 58

GOF mutation of ras gene

Answer 58

Intermediate adenoma

Question 59

Loss of mutation of p53

Answer 59

results in carcinoma

Question 60

HER2 overexpression

Answer 60

Breast cancer responsiveness to anti-hormone therapy