A team of researchers at the University of Kansas has identified a possible genetic factor underlying specific language impairment (SLI), a communication disorder whose cause has long stumped researchers. SLI typically entails delayed language development in early childhood. School-aged children with SLI often begin speaking later than the average child and may struggle with comprehension of spoken language, and utterances may appear somewhat stunted and immature. The disorder can be difficult for clinicians to properly diagnose; however, a recent study published in Brain Sciences suggests that a particular variation of the gene BUD13 could be implicated in its diagnosis.
“It can be hard to identify these children, but they might face problems speaking and learning grammar and not be very talkative—but they’re otherwise typical children,” said M. Hashim Raza, a co-author on the study. “If we talk about their nonverbal IQ level, they fall into the in-the-average range, and sometimes we see their nonverbal IQ level is even higher than in average people.” Somewhere between 7% and 10% of kindergartners are estimated to have SLI, according to the researchers. While it can be difficult to diagnose individuals with SLI based on a child’s performance on linguistic assessments alone, the discovery of a potential genetic marker could make diagnosis a bit more straightforward.
The recent study focused on an individual family with higher-than-average prevalence of SLI. Of the ten children in the family, seven had SLI (this family is also part of another larger, ongoing study of potential genetic factors underlying the disorder). After identifying a mutation in BUD13 among the family members, the researchers then compared the variant with the gene of 175 unrelated individuals with a prior diagnosis of SLI.
By examining BUD13 in the other subjects, the researchers identified 15 other variants, indicating that the gene could be involved in the development of SLI. Another recent study has also implicated BUD13 in language development and communication disorders. Given that early diagnosis and intervention for children with SLI can help significantly mitigate the effects of the disorder, the researchers believe that future research into BUD13’s role in SLI could be particularly useful for streamlining the diagnosis process.
“Based on the genetic evidence in our family-based study and previous reports, we suggest BUD13 regulates the expression of other genes, predominantly neuronal genes, and is an essential new target gene for SLI,” Raza said. AW