Sotos Syndrome

Question 1

information

Answer 1

• congenital overgrowth disorder - recognised from birth
• 1/14000
• have the genetic mutation located on chromosome 5q35
• haploinsufficiency of nuclear receptor binding SET domain protein 1 (NSD1 gene)
• 90% of cases (other 10% not known)
• severity of phenotype = variable

Question 2

cardinal features

Answer 2

• overgrowth
• macrocephaly (height and/or head circumference in 97th percentile)
• advanced bone age
• characteristic facial appearance (sparse hair, prominent jaw, frontal bossing)
• intellectual disability

Question 3

clinical features

Answer 3

• scoliosis
• seizures
• cardiac abnormalities
• renal anomalies
• hyper-laxity (joint hyper mobility)

Question 4

cognitive abilities

Answer 4

Lane, Milne and Freeth (2016)

• intellectual disabilities
• 25 studies assessing IQ (range = 21-113)
• verbal IQ tends to be higher than performance IQ
• not explored in detail

majority of individuals with Sotos in the mild intellectual ability (IQ = 50-69) or the borderline ability (IQ = 70-84) range.

Question 5

language abilities

Answer 5

Finegan et al (1994)

• delays reported in speech and language (11 studies)
• language abilities in Sotos individuals consistent with general level of intellectual functioning

Question 6

behavioural profile

Answer 6

• self injurious behaviour
• destruction of property
• impulsivity or over-reactivity
• social interaction impairment
• preference for routine, repetitive questions and repetitive phrase/signing

Lane, Milne and Freeth (2016)

• 14 studies
• 6 reported aggression and tantrums
• ASD = 4
• Anxiety = 2
• ADHD = 8

Sheth et al (2015) - syndrome specific behavioural profile not clear

Question 7

differences in the brain

Answer 7

Beuhler, Lin and Cole (1997)

• MRI brain scans of 40 Sotos children
• abnormalities of the corpus collosum (connecting hemispheres)
• enlarged ventricles
• inadequate development of posterior white matter
• delayed and disturbed development of brain
• normal size brains in large heads

Question 8

ASD in Sotos

Answer 8

Lane, Milne and Freeth (2017)

• used social responsiveness scale (questionnaire)
• impulsivity and overreactivity
• social interaction impairment
• preference for routine, repetitive questions and phrases
• 83.33% met DSM5 clinical cut off for ASD (5-19 highest ASD scores)

5 identifiable factors

• emotion recognition
• social avoidance
• interpersonal relatedness
• insistence on sameness
• repetitive mannerisms
• does this suggest genetic implications in ASD? (5q35 = ASD symptomatology)

Question 9

cognitive profile

Answer 9

Lane, Milne and Freeth (2018)

• British abilities scales (BAS3)
• 14.6 year age range
• <10% falling in average range
• 20% in borderline
• 70% in disability range
• spatial WM (recognising design) strength
• logic of pattern construction and manipulating information spatial skills tended to be worse
• strength in visuospatial memory and verbal skills
• weakness in non verbal reasoning and quantitative reasoning