[Clinical and genetic characteristics of children with Pitt-Hopkins syndrome caused by TCF4 gene variants].

The clinical data of children with Pitt-Hopkins syndrome (PTHS) who were treated in the Affiliated Women and Children's Hospital of Ningbo University from September 2022 to January 2024 were retrospectively included. The patients were followed up to June 2024, and their clinical and genetic characteristics were analyzed. A total of 4 children were included, 2 males and 2 females, with a diagnostic age [M (Q₁, Q₃)] of 22 (10, 32) months. All the patients presented with typical facial and overall developmental delay (developmental, motor and language delay). The 4 patients were found to harbor de novo heterozygous variants of the TCF4 gene, including the c.990G>A(p.S330S), c.1417_1418delinsT (p.Pro473ArgfsTer15), c.1028C>G (p.S343*) and c.500-2delinsTC. After 15 months of follow-up, all 4 patients received early rehabilitation treatment, and their gross motor function improved to varying degrees, while 3 patients had no improvement in language function. TCF4 gene variation in 4 children had phenotypic heterogeneity, and the main clinical manifestations were developmental delay, language development disorder and special facial features. Among the gene variation types, there was 1 case each of synonym variation, frameshift variation, nonsense variation and splicing variation.