Neurodevelopmental

Question 1

[Gen/ND/Basic]

Most common inherited intellectual disability?

Answer 1

Fragile X syndrome

Question 2

[Gen/ND/Basic]

Percentage of chromosomal abnormality in mild intellectual disability?

Answer 2

4-8%

Question 3

[Gen/ND/Basic]

Percentage of chromosomal abnormality in severe intellectual disability?

Answer 3

40-45%

Question 4

[Gen/ND/MDS]

Characteristics of Miller-Dieker syndrome? (2)

Answer 4

1. Lissencephaly: severe intellectual disability, developmental delay, seizures, spasticity, hypotonia
2. Distinctive facial features: a prominent forehead, midface hypoplasia, a small, upturned nose, low-set and abnormally shaped ears, micrognathia

Question 5

[Gen/ND/MDS]

Genetic cause of Miller-Dieker syndrome?

Answer 5

Partial deletion of 17p13.3, including PAFAH1B1 and YWHAE

Question 6

[Gen/ND/Rett]

Characteristics of Classic Rett syndrome (female)? (3)

Answer 6

1. progressive neurodevelopmental disorder
   normal psychomotor development during the first six to 18 months of life
   followed by a short period of developmental stagnation
   then rapid regression in language and motor skills
   long-term stability
2. repetitive, stereotypic hand movement
3. screaming and inconsolable crying, autistic features, panic-like attacks, bruxism, episodic apnea and/or hyperpnea, gait ataxia and apraxia, tremors, seizures, and acquired microcephaly.

Question 7

[Gen/ND/Rett]

Genetic cause of Rett syndrome?

Answer 7

MECP2

Question 8

[Gen/ND/Aicardi]

Triad of Aicardi syndrome?

Answer 8

1. Agenesis of the corpus callosum
2. Infantile spasms
3. Chorioretinopathy

Question 9

[Gen/ND]

Name of syndrome?

1. Distinctive facial features
   downslanted palpebral fissures
   low-hanging columella
   high palate
   grimacing smile
   talon cusps
2. Broad and often angulated thumbs and halluces
3. Short stature: height, weight, and head circumference percentiles rapidly drop in the first few months of life
4. Moderate-to-severe intellectual disability

Answer 9

Rubinstein-Taybi syndrome
(CREBBP or EP300)