Mental health and behavioural problems in children with XXYY: a comparison with intellectual disabilities.
XXYY syndrome gives boys with ID an extra layer of severe tantrums that you won’t predict from IQ alone.
01Research in Context
What this study did
Hatfield et al. (2019) compared boys who have both XXYY syndrome and intellectual disability with boys who have other causes of ID.
All boys were matched for IQ level so the team could isolate the extra risk that comes from the XXYY genotype.
Parents filled out rating scales about temper outbursts, mood, and daily living skills.
What they found
The XXYY group had more frequent and more intense temper outbursts than the IQ-matched peers.
Low IQ alone did not explain the difference; the extra Y chromosome added its own punch.
How this fits with other research
Jennett et al. (2003) already showed that male sex plus severe ID raises behavior-risk flags. R et al. extend that picture by naming a rare genotype that can hide behind those same flags.
Myrbakk et al. (2008) found psychiatric symptoms often drive screaming or self-injury in ID. R et al. agree, but spotlight XXYY as one specific medical reason to look deeper.
Chadwick et al. (2000) saw no link between daily-living skill deficits and tantrums in severe ID. R et al. now show that when the tantrums are unusually fierce, think XXYY first—skills deficits may not be the culprit.
Why it matters
If a boy with ID shows explosive, lengthy meltdowns that outrun his cognitive level, add XXYY to your differential. A quick genetics referral can end the diagnostic odyssey and open doors for targeted medical and behavioral plans. Meanwhile, beef up antecedent strategies—shorter tasks, clear visuals, and sensory breaks—because these kids tire faster and escalate quicker than their IQ peers.
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02At a glance
03Original abstract
BACKGROUND: The phenotype of children with XXYY has predominantly been defined by comparison to other sex chromosome aneuploidies trisomies affecting male children; however, the intellectual ability of children with XXYY is lower than children with other sex chromosome aneuploidies trisomies. It is not known to what extent the phenotype identified to date is specific to XXYY, rather than a reflection of lower IQ. This study evaluates the mental health and behaviour of children with XXYY, in comparison to children with intellectual disabilities of heterogeneous genetic origin. METHODS: Fifteen children with XXYY and 30 controls matched for age (4-14 years), sex and intellectual ability were ascertained from the IMAGINE ID study. IMAGINE ID participants have intellectual disabilities due to genetic anomalies confirmed by National Health Service Regional Genetic Centre laboratories. The mental health and behaviour of participants was examined with the Development and Well-being Assessment and the Strengths and Difficulties Questionnaire. RESULTS: Children with XXYY experienced significantly more frequent and intense temper outbursts than the control group. CONCLUSION: Our results suggest that temper outbursts may be specifically associated with the XXYY phenotype. These problems have a significant impact on the daily lives of boys with XXYY and their families. It is crucial to ensure that families are well supported to manage these difficulties.
Journal of intellectual disability research : JIDR, 2019 · doi:10.1111/jir.12607