p.319 + genes pwpt & articles

Question 1

children should have HL diagnosed by

Answer 1

3 months of age

Question 2

high-risk conditions

Answer 2

• ECMO or chemotherapy
• Cytomegalovirus infection
• Syndromes that have progressive HL
• Neurodegenerative disorders
• Trauma
• Postnatal infections associated w/ SNL HL
• caregiver concern
• Family Hx of HL

Question 3

ECMO stands for

Answer 3

Extra Corporeal Membrane Oxygenation

Question 4

ECMO is

Answer 4

procedure in which a machine outside of body delivers oxygen to a patient’s blood much like heart and lungs are supposed to (typically for infants in NICU who have health conditions complicating heart and/or lung fx)

Question 5

cytomegalovirus

Answer 5

a member of the herpes virus family

One of the most common congenital infections & a leading cause of hearing loss at birth

Question 6

If baby’s hearing loss is conductive

Answer 6

child may be referred to otolaryngologist and/or otologist

Question 7

if baby’s HL is SL,

Answer 7

infant must be evaluated by otolaryngologist who specializes in children with HL
AND
infant & family should be referred for Genetics Consultation and to pediatric ophthalmologist for Visual Acuity Examination

Question 8

origin of congenital or early-onset deafness

Answer 8

More than half are Genetic in origin

Question 9

% of syndromic and nonsyndromic congenital genetic HL

Answer 9

25% syndromic

75%Nonsyndromic

Question 10

Syndromic HL

Answer 10

occurs with other signs & symptoms

Question 11

nonsyndromic HL

Answer 11

usually occurs as the only disability

Question 12

chromosomal abnormalities

Answer 12

occur when there is either too much or too little genetic information
OR
material that is in wrong place

Question 13

Genetic abnormalities also known as

Answer 13

mutations

Question 14

genetic abnormalities

Answer 14

classified based upon whether they are located on an autosome or sex chromosome AND by inheritance pattern

Question 15

dominant transmission

Answer 15

requires only one gene for the trait to be passed on

Question 16

recessive transmission

Answer 16

requires that two copies of a gene are needed for a trait to be passed on

Question 17

autosomal dominant disorders

Answer 17

have an inheritance pattern in which one parent has the genetic mutation,
expresses the disorder, and
has a 50% chance of passing it on to his or her children.

Question 18

genotype

Answer 18

when a person has a trait in his or her genes (but doesnt necessarily present the trait)

Question 19

phenotype

Answer 19

when a person presents the trait that in his or her genes

Question 20

autosomal dominant HL

Answer 20

Not a surprise; knows it “runs in the family”

Question 21

autosomal dominant HL is presents itself in

Answer 21

mild or severe form (variation in expressivity)

Question 22

decreased penetrance

Answer 22

mild form of autosomal dominant disorder

Question 23

autosomal recessive disorders

Answer 23

occurs when both parents are carriers of the genetic mutation, but
usually do not express it, and
have a 25% chance of having a child with the disorder, 50% chance of the child being a carrier, and 25% chance of child being normal.

Question 24

autosomal recessive HL

Answer 24

is usually a surprise to parents

Question 25

most common nonsyndromic cause of genetic HL

Answer 25

mutation of the connexin 26 gene (GJB2) (inherited mostly in autosomal recessive mode)

Question 26

dual sensory impairment

Answer 26

simultaneous ocular and auditory impairment

Question 27

a recessively transmitted genetic condition that includes congenital HL and a progressive loss of vision (dual sensory impairment)

Answer 27

Usher syndrome

Question 28

most common sensory impairment in humans

Answer 28

deafness

Question 29

incidence of HL in children

Answer 29

1:1000

Question 30

how many genes involved in HL?

Answer 30

many different genes involved, but single gene mutations are most common

Question 31

exogenous

Answer 31

outside the genes-acquired

Question 32

endogenous

Answer 32

inside the genes

Question 33

examples of exogenous causes of HL

Answer 33

- Ototoxicity - Excessive Noise Exposure - Inflammatory disease - Trauma or Injury

Question 34

examples of endogenous causes of HL

Answer 34

Inherited trait- (Genetic)

Question 35

HL can be characterized as

Answer 35

congenital (at birth) hereditary (genetic) acquired (exogenous)

Question 36

Approx 1/2 of all Auditory disorders are due to

Answer 36

Hereditary factors (endogenous)--genetic causes

Question 37

Approx___#__ distinct syndromes can include hearing impairment

Answer 37

400

Question 38

Pendred syndrome

Answer 38

- Thyroid/goiter - abnormality in iodine - severe HL overe 50% of the time - need more comprehensive blood test to detect - hearing problems at birth, gets worse in childhood - Hearing deteriorates from minor knocks to head (mild loss can become profound if bumped into at school) - swelling at neck caused by enlarged thyroid

Question 39

Usher syndrome

Answer 39

Can leave people deaf & produce HL Have 10 diff genes that cause mutation Most severe & slow deterioration of sight & loss of vision by age 10 & profound HL at birth *early cochlear implantation would be crucial due to loss of vision

Question 40

Osteogenesis Imperfecta (OI)

Answer 40

Fractures in the absence of trauma (can be seen in family Hx) - mobility impairments - short stature (child not growing) - predisposition to fractures - little blue lining in pupil * Has Disorder of the Sensory System - Slow down of axonal to axonal reception - problems w/ walking & balance

Question 41

Modes of inheritance of hereditary deafness

Answer 41

``` Dominant Recessive X-linked Mitochondrial or other ```

Question 42

One parent exhibits the inherited trait 50% chance that inherited trait will be transmitted Presumed to cause 20% of endogenous deafness

Answer 42

Dominant inheritance

Question 43

- Exhibits the inherited trait when the individual carries 2 similiar abnormal genes (1 from each parent) - if no abnormal gene exists, child is normal - if 1 abnormal gene exists, child is carrier of trait - if 2 abnormal genes exist, child is carrier and exhibits - Account for as much as 80% of childhood deafness

Answer 43

hereditary deafness

Question 44

Defective traits are located on the X chromosome Males affected through carrier females Approx 2-3%deafness occurs

Answer 44

X-linked

Question 45

Small organelles in our cells that have their own DNA are known as mtDNA (we inherit all of our mtDNA from our mothers)

Answer 45

Mitochondrial

Question 46

doesnt follow same statistical probability as dominant/recessive patterns

Answer 46

mitochondrial

Question 47

abnormal transcription (missense mutation)

Answer 47

1 letter is replaced w/ incorrect chemical unit

Question 48

nonsense mutation

Answer 48

early stop in transcription

Question 49

Connexin 26 genes can be

Answer 49

recessive or dominant

Question 50

Hair cell degeneration & hereditary deafness

Answer 50

Hair cell degeneration not normally cause of hereditary deafness. hair cells may have developmental or functional defects that cause hearing impairment & lead to 2ndary hair cell degeneration

Question 51

gene therapy

Answer 51

permit productions or repression of 'proteins' - slow or increase rate of cell growth - inhibit or induce viral replication - increase or decrease cell death

Question 52

gene mapping

Answer 52

identifying the chromosomal location of the gene

Question 53

localization

Answer 53

isolating the defective gene (which may be in more than 1 place)

Question 54

limitations of gene Tx development

Answer 54

* no side effects of a treatment be worse than disease being treated * Hearing disorders tend not to be life threatening

Question 55

Studies on gene Tx

Answer 55

- current studies involve genes that protect cochlea from degeneration - difficult to find gene therapy approaches that can repair developmental defects in the embryo (complex development of inner ear) - normally deals with genetic defects that result in degeneration of cochlear structures AFTER they have been developed

Question 56

Genes are composed of a specific sequence of units of the following chemical units

Answer 56

Adenine (A) Guanine (G) Cytosine (C) Thymine (T)

Question 56

Genes are composed of a specific sequence of units of the following chemical units

Answer 56

Adenine (A) Guanine (G) Cytosine (C) Thymine (T)

Question 57

genes involved in the structure & f(x) of the ear

Answer 57

10% of 30,000 genes

Question 57

genes involved in the structure & f(x) of the ear

Answer 57

10% of 30,000 genes

Question 58

% of endogenous & exogenous causes of HL according to ASHA leader

Answer 58

50-60% endogenous (hereditary) | 40-50% exogenous (acquired)

Question 58

% of endogenous & exogenous causes of HL according to ASHA leader

Answer 58

50-60% endogenous (hereditary) | 40-50% exogenous (acquired)

Question 59

% of non-syndromic HL according to ASHA leader

Answer 59

60-70%

Question 59

% of non-syndromic HL according to ASHA leader

Answer 59

60-70%

Question 60

% of syndroming HL according to ASHA leader

Answer 60

30-40%

Question 60

% of syndroming HL according to ASHA leader

Answer 60

30-40%

Question 61

syndromic HL

Answer 61

HL from a gene that affects multiple organs

Question 61

syndromic HL

Answer 61

HL from a gene that affects multiple organs

Question 62

When recessive genes for deafness are located on X chromosome

Answer 62

trait is inherited as X-linked recessive

Question 62

When recessive genes for deafness are located on X chromosome

Answer 62

trait is inherited as X-linked recessive

Question 63

mitochondrial inheritance

Answer 63

inheritance of a genetic mutation in the genes contained w/in mitochondria (only inherited from mother-egg cell)

Question 63

mitochondrial inheritance

Answer 63

inheritance of a genetic mutation in the genes contained w/in mitochondria (only inherited from mother-egg cell)