Genetic Syndromes Affecting Movement

Question 1

Codon

Answer 1

Triplet sequence of nucleotides, determines specific AA that is inserted into a protein

Question 2

Locus

Answer 2

Specific location of a gene on a chromosome

Question 3

Polymorphism

Answer 3

Altered gene sequence that does not cause disease

Question 4

Single point mutation

Answer 4

Base pair substitution that may lead to AA change

Question 5

Deletion or insertion mutation

Answer 5

May result in missing or extra AA potential changes all down stream AA

Question 6

Trisomy 21

Answer 6

Down syndrome

Question 7

Trisomy 18

Answer 7

Edwards syndrome

Second most common trisomy observed in babies

Question 8

Trisomy 18 survival

Answer 8

Edwards
Mean survival is 2 weeks
90% die in first year

Question 9

Cri du chat syndrome

Answer 9

85% due to spontaneous deletion
Cat like cry in infant, LBW, hypotonia, feeding difficulties, failure to thrive, microcephalic, small jaw, wide mouth wide set eyes, w/ downward sloping palpebral fissures, epicanthic folds, strabismus, low set ears, broad nasal ridge

Question 10

Cri du chat characteristics

Answer 10

Clumsiness and hyperactivity w/ repetitive body movements
Chronic sleep disturbances
Mod to sever intellectual disabilities
50% can comm by age 10
Self injurious, hypersensitivity to sound, obsessive attachment to objects

Question 11

Syndromes w/ deletion of long arm chromosome 15

Answer 11

Prader-will I syndrome (father)

angel man syndrome (mother)

Question 12

Prader wili syndrome infancy

Answer 12

Diminished fetal activity, respiratory and feeding difficulties in infancy
Excessive eating

Question 13

Prader Willi cog

Answer 13

Intelligence range form normal to low/mod disability
Behavioral: tantrum, stubbornness, manipulative, autism, ADHD, OCD
Motor milestones twice typical

Question 14

Prader wili morphology

Answer 14

hypotonia, 
decreasede pigment of skin and eyes
Short stature, 
small hands and feet, 
small genitalia, 
hypogonadism

Question 15

Angel man syndrome

Answer 15

Severe learning difficulties, ataxia with jerky movevements, puppet like gait, seizure disorder, sleep disorder
Frequent and sometimes inappropriate laughter
Expressive speech is rare
Sign language recommended

Question 16

Angelman subtle dystrophin facial features

Answer 16

Wide
Smiling mouth 
Maxillary hypoplasia
Prominent chin
Deep set, often pale blue eyes

Question 17

X linked recessive disorders

Answer 17

Duchenne MD
Hemophilia A
May skip a generation w/ females as carriers

Question 18

X linked dominant

Answer 18

Fragile x

Rett syndrome

Question 19

most common recessive x linked disorder

Answer 19

Duchenne MD

Question 20

defective lack of clotting factor VII

Answer 20

Hemophilia A

Question 21

Most common type of inherited intellectual disability

Answer 21

Fragile X

Question 22

Fragile x

Answer 22

Females more midly affected

Delay in language/conversational speech

Question 23

Fragile x cog

Answer 23

Cog dysfunctions, 
ADHD 
Autism 
Anxiety
Epilepsy
Abnormal gaze
Stereotypical hand flapping/biting

Question 24

Fragile x facial features

Answer 24

Elongated faces
Large ears
Prominent mandible

Question 25

Fragile x motor

Answer 25

Hypotonia Joint hypermobility Tactile defensiveness Early motor developmental delay

Question 26

Rett syndrome

Answer 26

``` Progressive neruodevelopmental Almost exclusively in females Normal preg Typical development til 6-19 mo <6m mild hypotonia, placid personality, weak suck and cry ```

Question 27

Rett stage 1

Answer 27

Early onset developmental stagnation Plateau in skills b/n 6-18m Head growth decelerates resulting in microcephalic

Question 28

Rett Stage 2

Answer 28

``` Rapid destructive phase (1-3 yrs) Stereotyped hand movement, wringing Ataxia, tremor, apraxia, intermitten esotropia, autistic like behavior, teeth grind, breathing, GERD, impaired bowel mobility Expressive and receptive lang imp Severe cog impair ```

Question 29

Rett stage 3

Answer 29

``` Begins b/n 2-10 yr Can last for many yrs Increased seizure Kyphoscoliosis and hand deformities must be managed aggressively Osteoporosis - fx risk Amb varies from non amb to (I) w/out AD ```

Question 30

Rett stage 4

Answer 30

Late motor deterioration (after age 10) May last years to decades Reduced mobility, muscle weakness, joint contractures and scoliosis.