loricrin keratoderma

Loricrin keratoderma (LK) is a rare autosomal dominant genodermatosis caused by LORICRIN gene mutations. The pathogenesis of the disease is not yet fully understood. So far, only 10 pathogenic variants in LORICRIN have been described, with all of them but one being deletions or insertions. The significance of rare nonsense variants remains unclear. Furthermore, no data regarding the RNA expression in affected patients are available. The aim of this study is to describe the two variants in the LORICRIN gene found in two distinct families: the novel pathogenic variant c...

Palmoplantar keratodermas (PPK) comprise a heterogeneous group of keratinization disorders that gradually progress during childhood, resulting in difficulties to establish a diagnosis and to identify a candidate gene for sequencing. Dermoscopic examination with staining of palmoplantar skin using a whiteboard marker, so-called "furrow ink test", could be a useful tool for differentiation between furrow and ridge in understanding the morphological characteristics of PPK. One of the striking features in autosomal dominant loricrin keratoderma (LK) is diffuse PPK with honeycomb pattern...

BACKGROUND: Loricrin keratoderma is a rare early-onset autosomal dominant skin disorder. At present, no clinical reports have been published on characteristics of progressive aggravation and late-onset. OBJECTIVES: To identified a new-found pedigree with c.323 G>C mutation leading to progressive aggravation and late-onset loricrin keratoderma. METHODS: Targeted next-generation sequencing of 267 genes associated with all skin abnormalities, sanger sequencing, and bioinformatics tools were used to identify the mutation in this new-found pedigree...

Palmoplantar keratodermas (PPK) comprise a heterogenous group of acquired and hereditary disorders marked by excessive thickening of the epidermis of palms and soles. Hereditary PPKs can be classified into 3 groups: 1) isolated non-syndromic PPKs; 2) complex non-syndromic PPKs associated with other ectodermal defects; and 3) syndromic PPKs associated with extracutaneous manifestations. All types of inheritance have been observed: autosomal dominant, autosomal recessive, X-linked recessive, and mitochondrial...

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BACKGROUND: Hyperkeratotic hand eczema (HHE) is a typical clinical hand eczema subtype with a largely unknown pathophysiology. OBJECTIVE: To investigate histopathology, expression of keratins (K), epidermal barrier proteins, and adhesion molecules in HHE. METHODS: Palmar skin biopsies (lesional and perilesional) were obtained from seven HHE patients and two healthy controls. Moreover, 135 candidate genes associated with palmoplantar keratoderma were screened for mutations...

Revertant mosaicism refers to a condition in which a pathogenic germline mutation is spontaneously corrected in somatic cells, resulting in the presence of two or more cell populations with different genotypes in an organism arising from a single fertilized egg. If the revertant cells are clonally expanded due to a survival advantage over the surrounding mutant cells, patients benefit from this self-healing phenomenon which leads to the development of milder-than-expected clinical phenotypes; in genetic skin diseases, patients with revertant mosaicism present with small islands of healthy skin...

Loricrin downregulation has been associated with age-related changes as well as inherited and inflammatory skin diseases. We hypothesize that changes in loricrin could be more related to altered barrier function and consequently disorders that affect epithelial cells, such as psoriasis, atopic dermatitis (AD), erythrokeratoderma, loricrin keratoderma (LK) and periodontitis. The aim of this review is to summarize what is known about the association between loricrin downregulation and epithelial-related disorders (ERDs)...

Revertant mosaicism is a phenomenon in which pathogenic mutations are rescued by somatic events, representing a form of natural gene therapy. Here, we report on the first evidence for revertant mosaicism in loricrin keratoderma (LK), an autosomal dominant form of ichthyosis caused by mutations in LOR on 1q21.3. We identified two unrelated LK families exhibiting dozens of previously unreported white spots, which increased in both number and size with age. Biopsies of these spots revealed that they had normal histology and that causal LOR mutations were lost...

No abstract text is available yet for this article.

BACKGROUND: Symmetrical acral keratoderma (SAK) is a rare skin disorder and its pathogenesis and inheritability are unknown. OBJECTIVES: To investigate the inheritance and pathogenesis of SAK. METHODS: Four SAK cases occurred in a four-generation Chinese family. Exome sequencing identified SNPs with potential SAK-related mutations, and a potentially responsible gene transcription factor 4 (TCF4) was identified. TCF4 was then sequenced in all 11 family members, and pedigree analysis was performed...

Palmoplantar keratoderma (PPK) is a heterogeneous group of hereditary and acquired disorders characterized by abnormal thickening of the palms and soles. There are three clinical patterns: diffuse, focal, and punctuate. Palmoplantar keratodermas can be divided into the following functional subgroups: disturbed gene functions in structural proteins (keratins), cornified envelope (loricrin, transglutaminase), cohesion (plakophilin, desmoplakin, desmoglein 1), cell-to-cell communication (connexins) and transmembrane signal transduction (cathepsin C)...

Keratodermas comprise a heterogeneous group of highly debilitating and painful disorders characterized by thickening of the skin with marked hyperkeratosis. Some of these diseases are caused by genetic mutation, whereas other forms are acquired in response to environmental factors. Our understanding of signaling changes that underlie these diseases is limited. In the present study, we describe a keratoderma phenotype in mice in response to suprabasal epidermis-specific inhibition of activator protein 1 transcription factor signaling...

Vohwinkel syndrome or keratoderma hereditaria mutilans is a rare autosomal dominant palmoplantar keratosis, which manifests in infants and becomes more evident in adulthood. Its mode of inheritance is autosomal dominant with mutation in loricrin and Connexin 26 genes. Patients with this mutation present hyperkeratosis of the palms and soles, constricting bands of the digits, usually on the fifth, and starfish-shaped hyperkeratosis on the dorsal aspects of the hands and feet. The disease mostly occurs in white women, where constricting fibrous bands appear on the digits and can lead to progressive strangulation and auto-amputation (pseudo-ain-hum)...

OBJECTIVE: To detect potential mutations of gap junction protein beta 2 (GJB2) and loricrin (LOR) genes in two patients with Vohwinkel syndrome. METHODS: Polymerase chain reaction and DNA sequencing were used for detecting potential mutations in the GJB2 and LOR genes. Parents of one patient and 50 healthy individuals were used as controls. RESULTS: A novel homozygous missense mutation (c.A796G) of LOR gene was detected in one patient. The same mutation was not found in the other patient, their relatives and the 50 healthy controls...

The ichthyoses are a heterogeneous group of monogenetically inherited disorders of cornification, and characterized clinically by scaling or hyperkeratosis. Historically, they were classified by clinical features and inheritance patterns. As a result of the recent molecular biological revolution, the ichthyoses are now recognized as comprising many diverse entities. Importantly, identical phenotypes may be caused by mutations in multiple genes, while mutations in a single gene may result in multiple and sometimes widely divergent phenotypes...

Hereditary palmoplantar keratodermas (PPK) comprise a clinically and genetically heterogeneous group of genodermatoses, which share the characteristic of impaired epidermal differentiation, resulting in prominent palmoplantar hyperkeratosis. Molecular genetic analyses have helped characterize the underlying genetic defects in an increasing number of hereditary PPKs over the past two decades, and thus a pathophysiological classificaiton seems more reasonable. Today PPK can be classified based on defects in keratins, loricrin, desmosomes, connexins and cathepsins...

Vohwinkel syndrome (mutilating and diffuse palmoplantar keratoderma) is associated with various extracutaneous features including icthyosis and deafness. Its mode of inheritance is autosomal dominant with mutation in loricrin and Connexin 26 genes. Here we report a mutilating and focal palmoplantar keratoderma in two siblings with congenital hypotrichosis and probably autosomal recessive inheritance that appears to be a new variant of Vohwinkel syndrome.

BACKGROUND: Progressive symmetrical erythrokeratodermia (PSEK) is a rare inherited cornification disorder characterized by symmetrical erythematous hyperkeratotic plaques. The genetic basis for PSEK is not clear. PSEK shares many clinical features with erythrokeratodermia variabilis (EKV), which is associated with mutations in genes coding for gap junction beta (GJB) 3 and 4. A mutation in the loricrin gene (LOR) was found in patients with PSEK, who were members of a family with Vohwinkel syndrome...

Loricrin is a major constituent of the epidermal cornified cell envelope. Recently, heterozygous loricrin gene mutations have been identified in two dominantly inherited skin diseases, Vohwinkel syndrome with ichthyosis and progressive symmetric erythrokeratoderma, collectively termed loricrin keratoderma. We generated stable HaCaT cell lines that express wild-type (WT) loricrin and a mutant form found in Vohwinkel syndrome with ichthyosis, using an ecdysone-inducible promoter system. The cells expressing the mutant loricrin grew more rapidly than those expressing WT loricrin after induction for 5 days...