Neurodevelopmental Phenotype Associated with TRIP12: Report of a Family Carrying the p.Asp1135Val Variant

Pathogenic variants in the TRIP12 gene are associated with Clark-Baraitser syndrome, a condition characterized by neurodevelopmental disorders, including intellectual disability, autism spectrum disorder (ASD), and speech delay. Phenotypic expression is variable, and facial features are not consistently present. Familial inheritance is rare.

Whole-exome sequencing (WES) was performed on a proband with speech disorder and ASD, as well as on her parents. Clinical assessment included developmental, cognitive, and physical evaluations.

A heterozygous missense variant c.3404A>T (p. Asp1135Val) in the TRIP12 gene was identified in both the proband and her father. Both presented with speech disorder and ASD without facial features or severe intellectual disability.

In line with recent genotype-phenotype studies, missense TRIP12 variants tend to be associated with milder neurodevelopmental presentations, typically characterized by mild to moderate intellectual impairment, variable autistic traits, limited or absent facial features, and a low incidence of epilepsy. This familial case further presents the phenotypic spectrum of TRIP12 missense variants and highlights that ASD and speech disorder may occur as isolated neurodevelopmental findings without syndromic features. The report reinforces the relevance of TRIP12 analysis in the differential diagnosis of ASD and language disorders, even in individuals lacking physical traits, supporting more accurate genetic counseling and broader awareness of inherited TRIP12-related conditions.