Work

CHAMP1-Related Neurodevelopmental Disorder: Two Turkish Cases with Novel Truncating Variants and Literature Review

Year: 2026

Type: article

Abstract: Introduction: -NDD; neurodevelopmental disorder with hypotonia, impaired language, and dysmorphic features; MIM: 616579) is a rare autosomal-dominant condition caused by de novo truncating variants leading to haploinsufficiency. The phenotype is characterized by global developmental delay, intellectual disability, severe speech impairment, hypotonia, distinctive craniofacial features, and variable multisystem involvement. Case Presentation: variants. Both presented with global developmental delay, profound speech impairment, hypotonia, postnatal growth impairment, and characteristic craniofacial features. Neuroimaging demonstrated normal findings in 1 patient and a thin corpus callosum in the other. Additional manifestations included high-grade vesicoureteral reflux in one individual and sensory dysregulation, reduced pain sensitivity, early-onset hyperphagia, and recurrent respiratory infections in the other. Perinatal complications were noted in one case; however, the overall phenotype was considered primarily attributable to the underlying genetic diagnosis. Exome sequencing identified heterozygous truncating variants, NM_032436.4:c.2081_2082del; p.Ser694* and NM_032436.4:c.2062dup; p.Glu688Glyfs*8, both confirmed as de novo and classified as likely pathogenic according to American College of Medical Genetics and Genomics (ACMG) criteria. Conclusion: and further delineate the phenotypic variability of this disorder, highlighting under-recognized systemic and behavioral features. Recognition of these additional clinical observations may facilitate earlier diagnosis and multidisciplinary management, although further studies in larger cohorts are required to clarify their clinical relevance.

Source: Molecular Syndromology

DOI: 10.1159/000551451

Authors: Zehra Manav Yigit, Pelin Ozyavuz Cubuk, Kamil Utku Bayrak, Mehmet Bugrahan Duz, Adnan Yuksel