Harlequin-type ichthyosis is a genetic disorder that results in thickened skin over nearly the entire body at birth. The skin forms large, diamond/trapezoid/rectangle-shaped plates that are separated by deep cracks. These affect the shape of the eyelids, nose, mouth, and ears and limit movement of the arms and legs. Restricted movement of the chest can lead to breathing difficulties. These plates fall off over several weeks. Other complications can include premature birth, infection, problems with body temperature, and dehydration. The condition is the most severe form of ichthyosis, a group of genetic disorders characterised by scaly skin.
Ichthyosis vulgaris is a skin disorder causing dry, scaly skin. It is the most common form, and one of the mildest forms, of ichthyosis, affecting around 1 in 250 people. For this reason it is known as common ichthyosis. It is usually an autosomal dominant inherited disease, although a rare non-heritable version called acquired ichthyosis exists.
Lamellar ichthyosis, also known as ichthyosis lamellaris and nonbullous congenital ichthyosis, is a rare inherited skin disorder, affecting around 1 in 600,000 people.
Keratin 1 is a Type II intermediate filament (IFs) of the intracytoplasmatic cytoskeleton. Is co-expressed with and binds to Keratin 10, a Type I keratin, to form a coiled coil heterotypic keratin chain. Keratin 1 and Keratin 10 are specifically expressed in the spinous and granular layers of the epidermis. In contrast, basal layer keratinocytes express little to no Keratin 1. Mutations in KRT1, the gene encoding Keratin 1, have been associated with variants of the disease bullous congenital ichthyosiform erythroderma in which the palms and soles of the feet are affected. Mutations in KRT10 have also been associated with bullous congenital ichthyosiform erythroderma; however, in patients with KRT10 mutations the palms and soles are spared. This difference is likely due to Keratin 9, rather than Keratin 10, being the major binding partner of Keratin 1 in acral keratinocytes.
Keratin, type I cytoskeletal 10 also known as cytokeratin-10 (CK-10) or keratin-10 (K10) is a protein that in humans is encoded by the KRT10 gene. Keratin 10 is a type I keratin.
Palmoplantar keratodermas are a heterogeneous group of disorders characterized by abnormal thickening of the stratum corneum of the palms and soles.
Hyperkeratosis is thickening of the stratum corneum, often associated with the presence of an abnormal quantity of keratin, and is usually accompanied by an increase in the granular layer. As the corneum layer normally varies greatly in thickness in different sites, some experience is needed to assess minor degrees of hyperkeratosis.
Genodermatosis is a hereditary skin disease with three inherited modes including single gene inheritance, multiple gene inheritance and chromosome inheritance. There are many different types of genodermatosis, the prevalence of genodermatosis ranges from 1 per 6000 people to 1 per 500,000 people. Genodermatosis has influence on the texture, color and structure of skin cuticle and connective tissue, specific lesion site and clinical manifestations on the body vary depending on the type. In the spite of the variety and complexity of genodermatosis, there are still some common methods that can help people diagnose. After diagnosis, different types of genodermatosis require different levels of therapy including interventions, nursing interventions and treatments. Among that, research of therapy for some new, complex and rare types are still in the developing stage. The impact of genodermatosis not only can be seen in body but also can be seen in all aspects of patients' life, including but not limited to psychological, family life, economic conditions and social activities. Accordingly, the patients need treatment, support and help in these areas.
Epidermis-type lipoxygenase 3 is a member of the lipoxygenase family of enzymes; in humans, it is encoded by the ALOXE3 gene. This gene is located on chromosome 17 at position 13.1 where it forms a cluster with two other lipoxygenases, ALOX12B and ALOX15B. Among the human lipoxygenases, ALOXE3 is most closely related in amino acid sequence to ALOX12B. ALOXE3, ALOX12B, and ALOX15B are often classified as epidermal lipoxygenases, in distinction to the other three human lipoxygenases, because they were initially defined as being highly or even exclusively expressed and functioning in skin. The epidermis-type lipoxygenases are now regarded as a distinct subclass within the multigene family of mammalian lipoxygenases with mouse Aloxe3 being the ortholog to human ALOXE3, mouse Alox12b being the ortholog to human ALOX12B, and mouse Alox8 being the ortholog to human ALOX15B [supplied by OMIM]. ALOX12B and ALOXE3 in humans, Alox12b and Aloxe3 in mice, and comparable orthologs in other in other species are proposed to act sequentially in a multistep metabolic pathway that forms products that are structurally critical for creating and maintaining the skin's water barrier function.
Congenital hemidysplasia with ichthyosiform erythroderma and limb defects is a genetic disorder with onset at birth seen almost exclusively in females. The disorder is related to CPDX2, and also has skin and skeletal abnormalities, distinguished by a sharp midline demarcation of the ichthyosis with minimal linear or segmental contralateral involvement.
Ichthyosis bullosa of Siemens is a type of familial, autosomal dominant ichthyosis, a rare skin disorder. It is also known as bullous congenital ichthyosiform erythroderma of Siemens or ichthyosis exfoliativa. It is a genetic disorder with no known cure which is estimated to affect about 1 in 500,000 people.
Congenital ichthyosiform erythroderma, also known as nonbullous congenital ichthyosiform erythroderma, is a rare type of the ichthyosis family of skin diseases which occurs in 1 in 200,000 to 300,000 births. The disease comes under the umbrella term autosomal recessive congenital ichthyosis, which include non-syndromic congenital ichthyoses such as harlequin ichthyosis and lamellar ichthyosis.
CYP4F22 is a protein that in humans is encoded by the CYP4F22 gene.
Neutral lipid storage disease is a congenital autosomal recessive disorder characterized by accumulation of triglycerides in the cytoplasm of leukocytes, muscle, liver, fibroblasts, and other tissues. It commonly occurs as one of two subtypes, cardiomyopathic neutral lipid storage disease (NLSD-M), or ichthyotic neutral lipid storage disease (NLSD-I) which is also known as Chanarin–Dorfman syndrome), which are characterized primarily by myopathy and ichthyosis, respectively. Normally, the ichthyosis that is present is typically non-bullous congenital ichthyosiform erythroderma which appears as white scaling.
Ichthyosis hystrix is a group of rare skin disorders in the ichthyosis family of skin disorders characterized by massive hyperkeratosis with an appearance like spiny scales. This term is also used to refer to a type of epidermal nevi with extensive bilateral distribution.
Keratitis–ichthyosis–deafness syndrome, also known as ichthyosiform erythroderma, corneal involvement, and deafness, presents at birth/infancy and is characterized by progressive corneal opacification, either mild generalized hyperkeratosis or discrete erythematous plaques, and neurosensory deafness. It is caused by a mutation in connexin 26.
Trichorrhexis invaginata is a distinctive hair shaft abnormality that may occur sporadically, either in normal hair or with other hair shaft abnormalities, or regularly as a marker for Netherton syndrome. The primary defect appears to be abnormal keratinization of the hair shaft in the keratogenous zone, allowing for intussusception of the fully keratinized and hard distal shaft into the incompletely keratinized and soft proximal portion of the shaft.
Ichthyosis prematurity syndrome (IPS) is a dermatological disease with known genetic causes. This syndrome is a rare subcategory of autosomal recessive congenital ichthyosis (ARCI). It is associated with complications in the mid-trimester of a pregnancy leading to premature births. Although most prevalent in individuals of Scandinavian origin, there have also been scattered cases in people of Japanese, Italian and Indian ethnicity. This disorder is also referred to as ichthyosis congenital type IV.
Ichthyosis en confetti, is a very rare form of congenital ichthyosis in which healthy patches of normal skin co-exist within the abnormal skin areas. The condition is caused by a frameshift mutation in the keratin 10 gene (KRT10); mutant keratin 10 accumulates in the nucleolus, a sub-nuclear structure, rather than within cellular intermediate filaments like the wild-type protein. Children with the condition exhibit red, flaky skin; however, for reasons not yet totally clear, wild type clonal patches of skin start to appear, in place of the red, flaky skin. Due to the clonal nature of the growth of the normal skin cells, it appears the patient is covered with confetti, hence the name of the condition. It has been hypothesized that this is the result of a combination of mitotic recombination and natural selection within the skin.
Nipa‐Like Domain‐Containing 4, also known as NIPAL4 or Ichthyin, is a gene that is predicted to code for a transmembrane protein with nine transmembrane domains. NIPAL4 codes for the protein magnesium transporter NIPA4, which acts as a Mg2+
transporter.
