Epigenetics and ASD

Question 1

ASD is characterized by

Answer 1

problems in social interactions, communication, or repetitive behaviors

Question 2

Rett syndrome

Answer 2

mutation in MECP2, gene regulates epigenetic information (X-linked)

Question 3

Most common mutation linked to ASD

Answer 3

15q11-13 deletion/duplication

Question 4

Why are epigenetic marks linked to neurodevelopment abnormalities?

Answer 4

plasticity; integrate genetic and environmental factors

Question 5

Early signs of ASD

Answer 5

no emotional display, no/regression of babbling and communication, no gesturing

Question 6

DSM-V criteria for ASD

Answer 6

social deficits and repetitive behavior or interests present in early childhood development, can’t be explained by intellectual disability (no genetic component)

Question 7

Deficits in social communication and social interactions

Answer 7

deficits in social-emotional reciprocity, deficits in communicative behaviors, deficits in developing, maintaining, and understanding relationships

Question 8

Restricted, repetitive patterns of behavior, interests, or activities

Answer 8

stereotyped repetitive motor movements, insistence on sameness or inflexibility to change in routine, ritualized patterns, restricted, fixated interests, hyper- and hyporeactivity to sensory input

Question 9

Incidence of ASD

Answer 9

1 in 88, Males > Females by 4X

Question 10

Neurological abnormalities

Answer 10

alterations in size and time course of development that affects the proper brain connectivity

Question 11

What areas are affected by ASD

Answer 11

cerebral cortex, amygdala, hippocampus, and corpus callosum

Question 12

ASD brain structure

Answer 12

abnormal cortical development, abnormal size of amygdala (mature size by age 8)

Question 13

Long-term consequences of ASD

Answer 13

not progressive, but life-long

Question 14

Co-morbitites with ASD

Answer 14

seizures, allergies, asthma, digestive disorders

Question 15

ASD etiology is considered to be a combination of

Answer 15

genetic and environmental factors

Question 16

ASD genetic component

Answer 16

not a single allele, rather a combination of predisposing alleles

Question 17

Copy number variation

Answer 17

10% ASD patients have de novo acquired ASD

Question 18

Angelman Syndrome

Answer 18

imbalanced imprinting, Chr15 (q11-13)

Question 19

Beckwith-Wiedemann Syndrome

Answer 19

imbalanced imprinting, Chr11 (p15)

Question 20

Fragile X Syndrome

Answer 20

loss of FMR1 expression

Question 21

Turner Syndrome

Answer 21

45, X in females

Question 22

Enivornmental Factors

Answer 22

viral infection, vaccination, chemical agent exposure, parental age, pharmaceutical exposure

Question 23

Epigenetics

Answer 23

integrates environmental influences and genetics by altering expression of genes without changing the primary sequence of DNA

Question 24

2 types of Epigenetic marks

Answer 24

post-translational modification of histones and DNA methylation

Question 25

What enzyme causes DNA methylation

Answer 25

DNA methyltransferases

Question 26

Site of DNA methylation

Answer 26

cytosines of CpG dinucleotides

Question 27

DNA Methylation INHIBITS

Answer 27

gene expression

Question 28

DNA Methylation works by

Answer 28

DIRECTLY preventing binding of TFs DIRECTLY recruiting factors that repress transcription INDIRECTLY recruiting methyl-CpG binding proteins/enzymes to alter chromatin structure

Question 29

Epigenome

Answer 29

differs in cell types/tissues to allow cells to express a particular set of genes

Question 30

Epimutations

Answer 30

may occur due to genetic mutations or environmental exposures (or randomly)

Question 31

Genomic Imprinting

Answer 31

epigenomic markers silence parent-of-origin-specific gene expression

Question 32

Imprinting is established in

Answer 32

germ lines and maintained throughout

Question 33

Imprinted domains

Answer 33

cluster of imprinted genes allows for shared common regulatory features

Question 34

Imprinted gene functions

Answer 34

most involved with embryonic development and growth (placental development), postnatal functions (suckling and metabolism)

Question 35

Parental conflict hypothesis

Answer 35

Paternal Expressed genes: growth and fitness and ind survival Maternal Expressed genes: growth limiting for mother's survival

Question 36

Imprinting disorders

Answer 36

Prader-willi, Angelman, Beckwith-Wiedemann, Silver-Russel

Question 37

Prader-Willi

Answer 37

paternal inheritance defect in 15q11-13 (paternal SNRPN and NDN, and maternal UBE3A)

Question 38

Angelman's

Answer 38

maternal inheritance defect in 15q11-13 (paternal SNRPN and NDN, and maternal UBE3A)

Question 39

Epigenetic etiology of ASD

Answer 39

clear association to epigenetics

Question 40

Epigenetic syndroms result from deregulation of

Answer 40

1. genes regulated by epigenetic markers | 2. genes involved in epigenetic mechanisms

Question 41

Uniparental disomy

Answer 41

both copies of chromosomal pair form 1 parent, chromosome carries imprinted genes will result in overexpression or silenced

Question 42

Chromosomal region 7q

Answer 42

linked to ASD, contians imprinted gene clusters

Question 43

Genes involved in brain function/dev

Answer 43

epigenetic markers can cause aberrant brain development when on genes involved

Question 44

ASD's causes are

Answer 44

multifactorial and epigenetic markers integrate the environmental influences

Question 45

State with highest incidence of ASD

Answer 45

Utah and NJ

Question 46

State with lowest incidence

Answer 46

WI, AL, and FL