Establishment and characterization of ZJUCHi003: an induced pluripotent stem cell line from a patient with Temple-Baraitser/Zimmermann-Laband syndrome carrying KCNH1 c.1070G > A (p.R357Q) variant

Pathogenic variants of the KCNH1 gene can cause dominant-inherited Temple-Baraitser/Zimmermann-Laband syndrome with severe mental retardation, seizure, gingival hyperplasia and nail hypoplasia. This study established an induced pluripotent stem cell (iPSC) line using urinary cells from a girl with KCNH1 recurrent/hotspot pathogenic variant c.1070G > A (p.R357Q). The cell identity, pluripotency, karyotypic integrity, absence of reprogramming virus and mycoplasma contamination, and differential potential to three germ layers of the iPSC line, named as ZJUCHi003, were characterized and confirmed. Furthermore, ZJUCHi003-derived neurons manifested slower action potential repolarization process and wider action potential half-width than the normal neurons. This cell line will be useful for investigating the pathogenic mechanisms of KCNH1 variants-associated symptoms, as well as for evaluating novel therapeutic approaches.

Potassium Channel KCNH1 Activating Variants Cause Altered Functional and Morphological Ciliogenesis

The primary cilium is a non-motile sensory organelle that extends from the surface of most vertebrate cells and transduces signals regulating proliferation, differentiation, and migration. Primary cilia dysfunctions have been observed in cancer and in a group of heterogeneous disorders called ciliopathies, characterized by renal and liver cysts, skeleton and limb abnormalities, retinal degeneration, intellectual disability, ataxia, and heart disease and, recently, in autism spectrum disorder, schizophrenia, and epilepsy. The potassium voltage-gated channel subfamily H member 1 (KCNH1) gene encodes a member of the EAG (ether-à-go-go) family, which controls potassium flux regulating resting membrane potential in both excitable and non-excitable cells and is involved in intracellular signaling, cell proliferation, and tumorigenesis. KCNH1 missense variants have been associated with syndromic neurodevelopmental disorders, including Zimmermann-Laband syndrome 1 (ZLS1, MIM #135500), Temple-Baraitser syndrome (TMBTS, MIM #611816), and, recently, with milder phenotypes as epilepsy. In this work, we provide evidence that KCNH1 localizes at the base of the cilium in pre-ciliary vesicles and ciliary pocket of human dermal fibroblasts and retinal pigment epithelial (hTERT RPE1) cells and that the pathogenic missense variants (L352V and R330Q; NP_002229.1) perturb cilia morphology, assembly/disassembly, and Sonic Hedgehog signaling, disclosing a multifaceted role of the protein. The study of KCNH1 localization, its functions related to primary cilia, and the alterations introduced by mutations in ciliogenesis, cell cycle coordination, cilium morphology, and cilia signaling pathways could help elucidate the molecular mechanisms underlying neurological phenotypes and neurodevelopmental disorders not considered as classical ciliopathies but for which a significant role of primary cilia is emerging.

[Hereditary gingival fibromatosis: a three-generation case report]

Hereditary gingival fibromatosis (HGF) is a familial hereditary disease; while it is rare and usually benign, it is also characterized by the slow and progressive development of gingival tissue. This paper reports on the clinical examina-tion and history of HGF in a family of patients.

[Hereditary gingival fibromatosis: a case report]

Hereditary gingival fibromatosis (HGF) is a rare hereditary condition characterized by a slow, progressive increase in the gingival tissue. A case of HGF was reported and relevant literature of HGF were reviewed.

A new case of Zimmermann-Laband syndrome with atypical retinitis pigmentosa

This paper reports a case study of a 10-year-old girl exhibiting symptoms of a Zimmermann-Laband syndrome (ZLS), including an ocular involvement not previously observed. In addition to the case reported, we have also discovered 21 patients described in the literature. Major clinical findings, defined as being present in more than 75% of the cases under discussion, are presented.

Idiopathic gingival fibromatosis associated with mild hypertrichosis

A case of gingival fibromatosis with hypertrichosis is reported in a 10 year old girl. The condition is a syndrome and presents as a triad of gingival fibromatosis, hypertrichosis and mental retardation. Following surgical management, no recurrence was seen in the immediate post-surgical period. Even if recurrence occurs excision is recommended as the psychological benefits resulting from cosmetic improvement outweigh the danger of recurrence.

Laband syndrome: a case report

A case of Laband syndrome in an 8-yr-old girl is presented. The case is sporadic. The patient manifests enlargement of the soft tissue of the hard palate and the gingiva, which partly or completely covers the crowns of the teeth and macroglossia. The cartilagenous part of the nose and the ears is large and soft. She has synophrys and thick, straight hair. The nails of the fingers and toes are dysplastic. The girl exhibits no other abnormality, except an IQ of 61.

[Hydantoin hyperplasia--the interesting case]

The author describes a case of excessive gingival hyperplasia in a 9-year-old girl under hydantoin medication. The hyperplasia of the gingivae inhibited the regular uptake of food and the eruption of the permanent teeth.