Search Results (3)

Background: 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. Methods: 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. Results: 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. Conclusions: 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. Full article

Clark–Baraitser syndrome is a rare autosomal dominant intellectual disability syndrome caused by pathogenic variants in the TRIP12 (Thyroid Hormone Receptor Interactor 12) gene. TRIP12 encodes an E3 ligase in the ubiquitin pathway. The ubiquitin pathway includes activating E1, conjugating E2 and ligating E3 enzymes which regulate the breakdown and sorting of proteins. This enzymatic pathway is crucial for physiological processes. A significant proportion of TRIP12 variants are currently classified as variants of unknown significance (VUS). Episignatures have been shown to represent a powerful diagnostic tool to resolve inconclusive genetic findings for Mendelian disorders and to re-classify VUSs. Here, we show the results of DNA methylation episignature analysis in 32 individuals with pathogenic, likely pathogenic and VUS variants in TRIP12. We identified a specific and sensitive DNA methylation (DNAm) episignature associated with pathogenic TRIP12 variants, establishing its utility as a clinical biomarker for Clark–Baraitser syndrome. In addition, we performed analysis of differentially methylated regions as well as functional correlation of the TRIP12 genome-wide methylation profile with the profiles of 56 additional neurodevelopmental disorders. Full article

The Thyroid hormone Receptor Interacting Protein 12 (TRIP12) protein belongs to the 28-member Homologous to the E6-AP C-Terminus (HECT) E3 ubiquitin ligase family. First described as an interactor of the thyroid hormone receptor, TRIP12’s biological importance was revealed by the embryonic lethality of a murine model bearing an inactivating mutation in the TRIP12 gene. Further studies showed the participation of TRIP12 in the regulation of major biological processes such as cell cycle progression, DNA damage repair, chromatin remodeling, and cell differentiation by an ubiquitination-mediated degradation of key protein substrates. Moreover, alterations of TRIP12 expression have been reported in cancers that can serve as predictive markers of therapeutic response. The TRIP12 gene is also referenced as a causative gene associated to intellectual disorders such as Clark–Baraitser syndrome and is clearly implicated in Autism Spectrum Disorder. The aim of the review is to provide an exhaustive and integrated overview of the different aspects of TRIP12 ranging from its regulation, molecular functions and physio-pathological implications. Full article