Behavioral Project Presentations

Question 1

What is the etiology of Lesch Nyhan Disease? Inheritance pattern? Gene?

Answer 1

Inborn error of purine metabolism that produces too much uric acid
X-linked recessive
HPRT1 pathogenic variants

Question 2

What are the signs/symptoms of Lesch Nyhan?

Answer 2

abnormal motor control, executive functions, and emotional regulation
gout, joint pain/swelling, hematuria, UTIs, orange sand in diapers

Question 3

What are the behavioral characteristics of Lesch Nyhan?

Answer 3

self-injurious behavior like repeated lip/finger/cheek/hand biting, head/limb banging, face scratching

Question 4

What is the etiology of Williams syndrome?

Answer 4

contiguous gene deletion on 7q, most cases are de novo though does have autosomal dominant inheritance pattern

Question 5

What are the signs/symptoms of Williams syndrome?

Answer 5

stellate irides, cardiovascular disease, mild intellectual disability, hypercalcemia, growth abnormalities

Question 6

What are the behavioral characteristics of Williams syndrome?

Answer 6

overly friendly, gregarious, empathetic, loquacious, sensitive to sounds

Question 7

What are the signs/symptoms of Smith-Magenis syndrome?

Answer 7

peripheral neuropathy, scoliosis and other skeletal anomalies, hearing loss, ocular abnormalities, short stature, GI problems, childhood obesity, delays/ID

Question 8

What are the behavioral characteristics of Smith-Magenis?

Answer 8

sleep disturbances, sensory issues, maladaptive behaviors, self-injurious behavior

Question 9

What is the etiology of Smith Magenis?

Answer 9

heterozygous deletion on 17p is responsible for majority of cases, though intragenic variants in RAI1 account for 5-10%

Question 10

What are the signs/symptoms of Angelman syndrome?

Answer 10

severe DD, ID, speech impairment, gait ataxia, tremor, seizures, microcephaly, scoliosis

Question 11

What are the behavioral characteristics of Angelman syndrome?

Answer 11

happy demeanor, excitable, frequent laughing, short attention span, atypical sleep, hand-flapping, putting things in their mouths, fascination with water

Question 12

What are the four mechanisms of Angelman syndrome?

Answer 12

1. imprinting center
2. paternal UPD
3. deletion of maternal copy o f UBE3A
4. intragenic mutation of maternal copy of UBE3A

Question 13

What are the genotype-phenotype correlations for FRAX?

Answer 13

55-200 repeats - premutation
>200 repeats - full mutation
45-54 repeats - intermediate

Question 14

What conditions are associated with premutation carriers of FRAX?

Answer 14

Fragile X-associated tremors/ataxia syndrome
Fragile X-associated primary ovarian insufficiency