A cross-sectional study of early language abilities in children with sex chromosome trisomy (XXY, XXX, XYY) aged 1–6 years

Abstract

Children with sex chromosome trisomy (SCT) are at increased risk for developing language difficulties. Earlier studies have reported that as many as 70-80% of individuals with SCT show some form of language difficulties. Language develops rapidly in the first years of life; knowledge about language development at an early age is needed. The present study aims to identify the language abilities of young children with SCT across multiple language domains and to identify the percentage of children that, according to clinical guidelines, have language difficulties. Children between the ages of 1-6-years (N SCT = 103, N controls = 102) were included. Nonverbal communication, early vocabulary, semantic, syntax, and phonological skills were assessed. Language difficulties were already present in 1-year-old children with SCT and across the age range in various language domains. Clinical classification showed that, depending on the assessed domain, 14.8-50.0% of the children scored below the 16 th percentile. There was no effect of time of diagnosis, ascertainment bias, research site, nor SCT specific karyotype (XXX, XXY, XYY) on language outcomes. Overall, language difficulties can already be present in very young children with SCT within various language domains. These findings appear to be robust within the SCT group. These results highlight the importance of monitoring both receptive and expressive language development already at the earliest stages of nonverbal communication. Finally, as early language skills are the building blocks for later social communication, literacy, and self-expression, studies that investigate the effect of early interventions on later language outcomes are warranted.

Language Development in the Second Year of Life: The Case of Children with Sex Chromosome Trisomies Diagnosed before Birth

“…Children with SCTs show a higher incidence of language delays and impairments [27][28][29][30], and their neuropsychological profile is similar to that of children with DLD (i.e., a significant impairment in verbal skills, with general intelligence usually in the normal range, but with the mean slightly shifted to the left). No significant differences among the three SCT karyotypes were found in the first stages of language development [21,31], though some differences in their profiles could emerge later. For instance, Lee et al [32] suggested that an additional X chromosome (as in triple X syndrome and Klinefelter syndrome) might have a greater effect on structural language abilities, whereas an additional Y (as in Jacobs syndrome) might have a higher impact on pragmatics.…”

“…Moreover, during a play session in interaction with a parent, these children produced a significantly lower proportion of verbal utterances, and a significantly higher number of pointing gestures than TD children [30]. As Urbanus et al [21] reported in their recent cross-sectional study on 103 children ranging in age from one to six years, the linguistic performance of individuals with SCTs showed large deviations from the control group on nearly all language domains, and the number of children who experience linguistic problems increased with age. Therefore, monitoring language development from the earliest stages of nonverbal communication is fundamental to identifying children at risk, and intervening when needed [21].…”

“…Specifically, a significantly lower number of children with SCTs than TD toddlers showed the ability to babble during a parent-child interactive play session; in addition, the frequency of production of canonical and reduplicated babbling was significantly lower in toddlers with SCTs than in the control group [27]. In the second year of life (11-23 months), children with SCTs (n = 35) showed poorer receptive and expressive semantic skills than TD peers, according to both parent reports and neuropsychological assessments [21]. Zampini, Draghi, et al [30], at two years of age, identified 60% of children with SCTs (n = 9 out of 15 children) as late-talking toddlers (i.e., children with a vocabulary size smaller than 50 words at 24 months).…”

“…Recent literature reports that a slowdown in language development could be highlighted from the first stages of acquisition in all of the SCTs [21,27]. As early as eight months of age, children with SCTs (n = 26) showed a delay in preverbal communicative skills.…”

“…Moreover, we aim to analyse the effects of early individual characteristics in determining children's vocabulary development within this biological condition. We chose to focus on this population since one of its most distinctive traits is the extra chromosome's impact on language development [21].…”