Cognitive-behavioural and autistic features of children with subtelomeric deletions

Background: Cognitive-behavioural features of children with subtelomeric deletions have, to date, not been systematically assessed. Methods: We examined 29 children with del2q37 [n = 7], del8p23 [n = 7], del11q25 [n = 3], or 4p16 [n = 12], from 9 sites in the US and Europe using a neuropsychological battery to evaluate cognitive ability, adaptive behaviour, emotionality and temperament, attentiveness/hyperactivity, and autistic-like features. Results: We found 10/29 (34%) of our sample with CARS scores ≥30. That is, more than a third of the sample could be diagnosed as autistic. Cognitive deficits ranged from low-normal to severe. In addition, each disorder was associated with a distinct cognitive-behavioural profile. Children with de11q25 had significantly higher cognitive abilities, while those with del4p16 were significantly lower. Adaptive behaviour was significantly higher among children with 11q25. Cognitive ability and adaptive behaviour profiles were also statistically significantly different among the groups. Attention deficits and hyperactivity [ADHD] were also noted in 14/29 [47%] of the sample of children assessed. Conclusions: The study of the behavioural phenotypes associated with subtelomeric deletions is starting to demonstrate behavioural phenotypes for rare genetic disorders.