Thanks to a long-read sequencing (LRS) approach, in this study, we have reported a molecularly solved case of a proband with a clinical diagnosis of Cornelia de Lange syndrome (CDLS), which is a multisystemic disorder whose causative molecular defects involve cohesin complex genes, with NIPBL located at 5p13.2 accounting for approximately 50%–60% of CDLS cases. Here, NIPBL is linked to Cornelia de Lange syndrome.