Genetics Flashcards
includes syndrome, sequence, association, and craniofacial malformations
normal human has __ total chromosomes
46
meiosis
genetic combination from female and male (each contribute 23 chromosomes)
female
XX
male
XY
each chromosome contains…
thousands of genes
genes
- contain DNA
- genes regulate growth and development of organisms during embryological development and after birth
true or false: children can be born with multiple birth anomalies
true
anomalies appear to be related and may be characterized as…
- syndromes
- sequences
- associations
syndromes
- multiple anomalies having a single pathological cause
- chromosomal or genetic based
sequences
a single malformation causes a pattern or sequence of anomalies
associations
- abnormalities that co-occur together by chance
- more frequently than alone
- no evidence of a casual effect
chromosomal syndromes
- deletion of whole chromosome
- addition of whole chromosome
- deletion part of chromosome
- addition part of chromosome
- restructured chromosome/s
- rearranged chromosome/s
gene disorders
- autosomal dominant
- autosomal recessive
- x-linked dominant
- x-linked recessive
autosomal dominant
only 1 copy of a disease allele is necessary
autosomal recessive
2 copies of disease allele required to be susceptible
x-linked dominant
only 1 copy of a disease allele on the x chromosome necessary to be susceptible
x-linked recessive
2 copies of a disease allele on the X chromosome required to be susceptible
syndromes that are associated with speech, language, and/or feeding difficulties
- Angelman syndrome
- Cri du Chat syndrome
- Fragile X syndrome
- Noonan syndrome
- Russel-Silver syndrome
- Treacher Collins syndrome
- Usher syndrome
- Apert syndrome
- Crouzon syndrome
- Moebius syndrome
- Pierre-Robin syndrome
- Stickler syndrome
- Trisomy 13
- Van der Woude syndrome
- CHARGE syndrome
- Down syndrome
- Nager syndrome
- Prader-Willi syndrome
- Tourette syndrome
- Turner syndrome
- Velocardiofacial syndrome
deletion of whole chromosome
- rare
- Turner syndrome: missing sex chromosome (female has X only)
addition of whole chromosome
- additional chromosome
- Down syndrome: trisomy 21
deletion of part of chromosome
- most common
- Cri du Chat: deletion of short arm chromosome 5)
addition (or part of) or rearrangement of chromosomes
most with chromosomal anomalies have craniofacial malformations
sequences that are associated with speech, language, and/or feeding difficulties
- Fetal Akinesia deformation
- Pierre Robin sequence
- Potter sequence
associations that are associated with speech, language, and/or feeding difficulties
- Schisis association
- VACTERL asssociation
an individual can have both a sequence and a syndrome
- syndromes, sequences, and associations are lifelong conditions
- no cure, but can be managed by varying degrees
Angelman syndrome
- UBE3A gene, chromosome 15
- developmental delay
- severe learning disability
- receptive language > expressive
- severe speech impairment
- ataxia
- delayed motor development
- seizures
Angelman syndrome: characteristics
- prominent forehead
- skull deformities
- large lower jaw
- small flattened nose
- low set ears
- wide eyes
- webbing of fingers and toes
- dental issues
CHARGE syndrome
CHD7 gene
C = coloboma of eye (defect in iris/retina)
H = heart defect
A = atresia choanal (blockage of nasal passage)
R = retarded growth
G = genital hypoplasia
E = ear abnormalities (sensorineural hearing loss)
Cri-du-Chat syndrome
- short arm of chromosome 5 deletion
- severe learning disability
- intellectual disability
- congenital heart disease
Cri-du-Chat syndrome: characteristics
- microcephalic (small head)
- short stature
- poor muscle tone
- weak/high pitched cry
- downward wide set eyes
Crouzon syndrome
- FGR2 gene
- may have normal intelligence or intellectual disability
- may have cleft lip and/or palate
Crouzon syndrome: characteristics
- premature fusion of bones of skull
- small head
- shallow bulging eyes
- “beaked” nose
- malformed teeth
- increased cranial pressure
Down syndrome
- extra chromosome: trisomy 21
- language/articulation deficits
- intellectual disability
- cardiac problems
- hearing loss
Down syndrome: characteristics
- upward slanted eyes
- small head
- mid face growth deficiency (flat face/small features)
- short neck
- hypotonia (low muscle tone)
Fragile X syndrome
- FMR1 gene, X chromosome
- learning disability (weak/paralyzed facial muscles)
- ADD/ASD
- pragmatic deficits
Fragile X syndrome: characteristics
- dysmorphic facial features
- long/thin face
- large ears
- prominent forehead
- hyperextended fingers
- fine and/or thin skin
Moebius syndrome
- cranial nerves VI and VII
- articulation deficits (weak/paralyzed facial muscles)
- feeding/swallowing issues
Moebius syndrome: characteristics
- affects muscles that control facial expression and eye movement
- chest muscles may be affected
- abnormalities of fingers
Nager syndrome
- SF3B4 gene
- articulation deficits (jaw/cheek deformities, cleft palate)
- conductive hearing loss
Nager syndrome: characteristics
- micrognathia (small jaw)
- malar hypoplasia
- hammer toes
Velocardiofacial syndrome
- missing small part of chromosome 22
- learning difficulties
- severe velopharyngeal insufficiency (resonance)
- cleft palate
Velocardiofacial syndrome: characteristics
- unique facial characteristics
- wide nose
- small ears
- microcephaly
- micrognathia
Williams syndrome
- deletion from chromosome 7 (26-28 genes)
- low IQ (high music/interpersonal skills)
- difficulty with conceptual/relational vocabulary
Williams syndrome: characteristics
- distinctive facial features
- short nose with broad tip
- wide mouth
- full lips
- small chin
- puffy eyes
- dental issues
- overly outgoing/friendly (extreme interest in others)
Fetal Akinesia Deformation sequence
- RAPSN or D0K7 gene
- articulation (may have cleft)
- intra-uterine growth restriction
Fetal Akinesia Deformation sequence: characteristics
- decreased fetal movement
- facial anomalies
- underdevelopment of lungs
Potter sequence
- may be genetic or by chance
- underdeveloped lungs, heart defects
Potter sequence: characteristics
distinct facial features:
- flat nose
- recessed chin
- skin folds
- low-set ears
Robin sequence
- S0X9 gene
- articulation deficits (cleft palate)
- hypernasality
- hearing loss
Robin sequence: characteristics
- micrognathia (underdeveloped lower jaw)
- restricted or hypo plastic
- mandible
- U-shaped cleft of soft palate
Schisis association
- unknown
- articulation deficits (if cleft palate present)
Schisis association: characteristics
occurs when 2 or more of following anomalies are present
- neural tube defects
- cleft lip/palate
- omphalocele (abdominal organs outside body at birth)
- congenital diaphragmatic hernia
VACTERL association
- unknown
V = vertebral abnormalities
A = anal atresia
C = cardiac defects
T = tracheal anomalies (TE fistula)
E = esophageal atresia
R = renal or kidney abnormalities
L = limb abnormalities
VACTERL association: characteristics
- facial asymmetry
- ear malformations
- tracheal stenosis
- absent/small lungs
cleft lip and palate
in typical development, fusion of primary + secondary palate occurs during 1st trimester
cleft
lack of fusion of orofacial structures (i.e., lips, alveolus, hard and/or soft palate)
classifications of clefts
- primary palate
- secondary palate
- isolated
- combination
- unilateral
- bilateral
- complete
- incomplete
classification of clefts: primary palate
lip, alveolus, and hard palate (anterior to incisive foramen)
classification of clefts: secondary palate
hard and soft palate (posterior to incisive foramen)
classification of clefts: isolated
cleft lip OR palate
classification of clefts: combination
cleft lip AND palate
classification of clefts: unilateral
left or right sided cleft
classification of clefts: bilateral
left and right sided cleft
classification of clefts: complete
entire length of palate (cleft extends into nose)
classification of clefts: incomplete
cleft does not extend into the nose
overt palatal cleft
- visibly open
- can be observed on intra-oral inspection
submucous cleft
cleft is covered by mucous membrane that lines roof of mouth
prevalence and incidence: most common
complete cleft of lip and palate (complete combination cleft)
prevalence and incidence: least common
isolated cleft of lip or palate
prevalence and incidence: males vs. females
- males: cleft lip and palate
- females: cleft palate only
~ _ in ___ births will be born with cleft lip and/or palate in the U.S.
1, 700
___ disorders most commonly present in clefts
speech
cleft lip and palate: speech sound disorders
- sensory-motor based phonetic errors
- linguistic based phonemic errors
- pressure sounds (stops, fricatives, affricates)
- may produce with weak pressure
- nasal emission: audible release of air through nose
- compensatory errors
cleft lip and palate: resonance disorders
- velopharyngeal insufficiency or dysfunction: opening between mouth and nose not closed properly
- hypernasality: excess nasal resonance on vowels/voiced sounds
- cul de sac resonance: sound is muffled due to some obstruction
cleft lip and palate: speech error types
- developmental errors
- obligatory errors
- compensatory errors
developmental errors
- variations also seen in speech of normally developing kids
- may or may not need therapy
obligatory errors
- structural abnormality (e.g., cleft) results in speech errors
- fix structure before therapy
compensatory errors
- incorrect placement compensates for structure
- traditional speech therapy
most common errors due to velopharyngeal dysfunction
- articulatory placement errors
- obligatory errors
- compensatory errors
articulatory placement errors
where sounds are made
obligatory errors
- if errors are consistent across all high pressure sounds
- result of velopharyngeal insufficiency
- need surgery to correct form before speech therapy
- function follows form
compensatory errors
- if errors are inconsistent, not on all pressure sounds
- result of mislearning
- phoneme specific nasal emission
- common compensatory errors
compensatory errors: result of mislearning
- adequate intra-oral pressure
- may benefit from speech therapy alone
- form compensated due to structure
compensatory errors: phoneme specific nasal emission
- error type
- individual produces a pressure speech sound/class of sounds as a nasal fricative
- result of mislearning and responsive to speech articulation therapy
compensatory errors: common
- glottal stops
- pharyngeal fricatives and stops
- nasal fricatives
- mid-dorsum palatal stops
cleft lip and palate: assessment
- motor: structure and function
- speech: articulation and resonance
- cognitive abilities (age appropriate)
- social skills: identify co morbidities
- feeding and swallowing
cleft lip and palate: treatment
- interdisciplinary team approach
- surgical repair: to correct structure
- speech therapy: reduce learned behaviors
- pre-surgical orthopedics
- treatment will vary based on type of errors
evaluation of resonance
- nasal futter test
- mirror test
- reading lists
nasal flutter test
- pinch nose during prolonged vowel
- a difference in resonance indicates a problem (e.g., VPI)
mirror test
- hold mirror under patient’s nose during pressure sounds
- look/listen for nasal emission
reading lists
- client reads word lists of minimal pairs (e.g., bad/mad)
- hypernasal: nasalization of non-nasals (e.g., bad/mad sounds like mad/mad)
- hyponasal: lacking nasal resonance (e.g., bad/mad sound like bad/bad)
compensatory treatment strategies
- initial target: stimulable sounds
- auditory discrimination –> phonetic placement –> multimodal cueing
cleft lip and palate: 3-6 months
repair of cleft lip
cleft lip and palate: 6-12 months
repair of cleft palate
cleft lip and palate: 12 months+
speech and language therapy
cleft lip and palate: 6-11 years
orthodontic interventions
cleft lip and palate: birth-21 years
ongoing treatment and management until about 21 years old
cleft lip and palate: interdisciplinary team
coordinator, surgeon, orthodontist, speech-language pathologist, +1 additional specialist:
- audiologist
- pediatric dentist
- geneticist
- neurosurgeon
- oral surgeon
- plastic surgeon
- pediatrician
- ophthalmologist
- otolaryngologist
- prosthodontist
- psychologist
- social worker
