Differences in speech and language abilities between children with 22q11.2 deletion syndrome and children with phenotypic features of 22q11.2 deletion syndrome but without microdeletion

• Speech and language delay (SLD) was detected in children with 22q11.2 microdeletion.
• SLD was detected in children with phenotype resembling 22q11.2DS but without microdeletion.
• Children with 22q11.2 microdeletion had more severe SLD compared to children with phenotype resembling 22q11.2DS but without microdeletion.
• 22q11.2 microdeletion contributes to SLD detected in children with 22q11.2DS.

Background22q11.2DS is the most common microdeletion syndrome in humans, usually associated with speech and language delay (SLD). Approximately 75% of children with 22q11.2 microdeletion have congenital heart malformations (CHM) which after infant open-heart surgery might lead to SLD.AimsThe purpose of this study was to determine whether factors associated with microdeletion contribute to SLD in children with 22q11.2DS.Methods and proceduresWe compared speech and language abilities of two groups of school-aged children: those with 22q11.2 microdeletion (E1) and those with the phenotype resembling 22q11.2DS but without the microdeletion (E2). An age-matched group of typically developing children was also tested.Outcomes and resultsThe obtained results revealed that children from group E1 have lower level of speech and language abilities compared to children from group E2 and control group. Additionally, mild to moderate SLD was detected in children from group E2 compared to children from the control group.Conclusions and implicationsThe obtained results imply that both CHM after infant open-heart surgery and other factors associated with 22q11.2 microdeletion, contribute to SLD in patients with 22q11.2 microdeletion. Based on this, we could postulate that there is/are some potential candidate gene(s), located in the 22q11.2 region, whose function could be important for speech and language development.