Language Profiles of School-Aged Children with 22q11.2 Copy Number Variants

Abstract

Although it is known that copy number variants (CNVs) on chromosome 22, such as 22q11.2 deletion (22q11.2DS) and 22q11.2 duplication (22q11.2Dup) syndromes, are associated with higher risk for neurodevelopmental issues, few studies have examined the language skills across 22q11.2Dup nor compared them with the 22q11.2DS. The current study aims to characterize language abilities in school-aged children with 22q11.2Dup (n = 29), compared to age-matched children with 22q11.2DS (n = 29). Standardized language tests were administered, assessing receptive and expressive language skills across different language domains. Results indicate that children with 22q11.2Dup demonstrate significantly more language problems compared to the general population. Mean language skills were not significantly different among children with 22q11.2 CNVs in this cohort. While children with 22q11.2DS demonstrated language difficulties starting at the word level, the most common language problems in children with 22q11.2Dup started at the sentence level. Importantly, both expressive and receptive language as well as lexico-semantic and morphosyntactic domains were impaired in children with 22q11.2 CNVs. Early identification, therapeutic intervention, and follow-up of language impairments in children with 22q11.2Dup are recommended to support language development and to reduce longitudinal impact of language and communicative deficits.

Keywords: 22q11.2 deletion syndrome; 22q11.2 duplication; communication; copy number variants; language.

Figure 1

Boxplots for CELF CLS composite scores across CNV groups and cohort sites. The dotted lines show norm group averages. The gray zones indicate the severity of the problems; the darker the gray, the more severe the difficulties: mild–moderate = light gray zone and severe = darker gray zone, based on clinical cut-off scores for the CELF. Abbreviations. CELF, Clinical Evaluation of Language Fundamentals (norm group average = 100, cut-off: <85 = mild–moderate (pc 16), <70 = severe (pc 2).

Figure 2

Boxplots for CELF Core Language Scores across groups (22q11.2DS and 22q11.2Dup).

Figure 3

Normative distributions of CELF Core Language Scores across groups (22q11.2DS and 22q11.2Dup). SD, standard deviation. The dashed line illustrates the normative distribution of the norm group (mean = 100, SD = 15). SD shifts are calculated in relation to the normative sample.