Waardenburg syndrome is a rare genetic disorder most often characterized by varying degrees of deafness, minor defects in structures arising from the neural crest, and pigmentation anomalies. The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The International Statistical Classification of Diseases and Related Health Problems 10th Revision (ICD-10) is a coding of diseases and signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or diseases, as classified by the World Health Organization (WHO). ... // E00-E35 - Endocrine diseases (E00-E07) Disorders of thyroid gland (E00) Congenital iodine-deficiency syndrome (E01) Iodine-deficiency-related thyroid disorders and allied conditions (E02) Subclinical iodine-deficiency hypothyroidism (E03) Other hypothyroidism (E030) Congenital hypothyroidism with diffuse goitre (E031) Congenital hypothyroidism without goitre (E032) Hypothyroidism due to medicaments and other... The International League of Dermatological Societies (ILDS) is a non-governmental organization affiliated with the World Health Organization. ... The International Statistical Classification of Diseases and Related Health Problems (most commonly known by the abbreviation ICD) provides codes to classify diseases and a wide variety of signs, symptoms, abnormal findings, complaints, social circumstances and external causes of injury or disease. ... The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. ... The Disease Bold textDatabase is a free website that provides information about the relationships between medical conditions, symptoms, and medications. ... MedlinePlus (medlineplus. ... eMedicine is an online clinical medical knowledge base that was founded in 1996. ... Medical Subject Headings (MeSH) is a huge controlled vocabulary (or metadata system) for the purpose of indexing journal articles and books in the life sciences. ... A genetic disorder is a condition caused by abnormalities in genes or chromosomes. ... This article discusses the way the word deaf is used and how deafness is perceived by hearing and Deaf communities. ... The neural crest, a component of the ectoderm, is one of several ridgelike clusters of cells found on either side of the neural tube in vertebrate embryos. ...

Eponyms and classification

It is named after Dutch ophthalmologist Petrus Johannes Waardenburg (1886-1979), who first defined it in 1951.^{[1] [2]} The condition he described is now categorized as WS1. Ophthalmology is the branch of medicine which deals with the diseases of the eye and their treatment. ...

WS2 was identified in 1971, to describe cases where "dystopia canthorum" did not present.^[3] WS2 is now split into subtypes, based upon the gene responsible. Front of left eye with eyelids separated to show medial canthus. ...

Other types have been identified, but they are less common.

Subtypes of the syndrome are traceable to different genetic variations:

There are several other names used. These include Klein-Waardenburg syndrome, Mende's syndrome II, Van der Hoeve-Halbertsma-Waardenburg syndrome, Ptosis-Epicanthus syndrome, Van der Hoeve-Halbertsma-Gualdi syndrome, Waardenburg type Pierpont^[4], Van der Hoeve-Waardenburg-Klein syndrome, Waardenburg's syndrome II, and Vogt’s syndrome. The Mendelian Inheritance in Man project is a database that catalogues all the known diseases with a genetic component, and - when possible - links them to the relevant genes in the human genome. ... Short and long arms Chromosome. ... Paired box (Pax) genes are a family of tissue specific transcription factors containing a PAIRED domain and usually a partial or complete homeodomain. ... Microphthalmia-associated transcription factor is a basic helix-loop-helix leucine zipper transcription factor. ... In chemistry, a ligand is an atom, ion, or molecule (see also: functional group) that generally donates one or more of its electrons through a coordinate covalent bond to, or shares its electrons through a covalent bond with, one or more central atoms or ions (these ligands act as a... Endothelin is a 21-amino acid vasoconstricting peptide that plays a key part in vascular homeostasis. ... Sox genes belong to a super-family of genes characterised by a homologous sequence called the HMG (high mobility group) box. ...

Incidence

Types I and II are the most common types of the syndrome, whereas types III and IV are rare. Overall, the syndrome affects perhaps 1 in 15,000 people. About 1 in 30 students in schools for the deaf have Waardenburg syndrome. All races and both sexes are affected equally. The highly variable presentation of the syndrome makes it difficult to arrive at precise figures for its prevalence. This article discusses the way the word deaf is used and how deafness is perceived by hearing and Deaf communities. ...

Symptoms

Symptoms vary from one type of the syndrome to another and from one patient to another, but they include:

• Very pale or brilliantly blue eyes, eyes of two different colors (complete heterochromia), or eyes with one iris having two different colours (sectoral heterochromia);
• A forelock of white hair (poliosis), or premature graying of the hair;
• Wide-set eyes (hypertelorism) due to a prominent, broad nasal root (dystopia canthorum—particularly associated with type I);
• Moderate to profound hearing impairment (higher frequency associated with type II); and
• A low hairline and eyebrows that touch in the middle.
• Patches of white pigmentation on the skin have been observed in some people. Sometimes, abnormalities of the arms, associated with type III, have been observed.
• Type IV may include neurologic manifestations.

Waardenburg syndrome has also been associated with a variety of other congenital disorders, such as intestinal and spinal defects, elevation of the scapula, and cleft lip and palate. For the tightly packed form of DNA, see Heterochromatin. ... Hypertelorism is an abnormally increased distance between two organs or bodily parts, usually referring to an increased distance between the eyes (orbital hypertelorism), seen in a variety of syndromes, including DiGeorge syndrome and Loeys-Dietz syndrome. ... In biology, pigment is any material resulting in color in plant or animal cells which is the result of selective absorption. ... For other uses, see Skin (disambiguation). ... Neurology is a branch of medicine dealing with disorders of the central and peripheral nervous systems. ... A congenital disorder is any medical condition that is present at birth. ... In anatomy, the intestine is the segment of the alimentary canal extending from the stomach to the anus and, in humans and other mammals, consists of two segments, the small intestine and the large intestine. ... The vertebral column seen from the side Different regions (curvatures) of the vertebral column The vertebral column (backbone or spine) is a column of vertebrae situated in the dorsal aspect of the abdomen. ... Left scapula - front view () Left scapula - rear view () In anatomy, the scapula, or shoulder blade, is the bone that connects the humerus (arm bone) with the clavicle (collar bone). ... Look up cleft lip and palate in Wiktionary, the free dictionary. ...

Inheritance

This condition is usually inherited in an autosomal dominant pattern, which means one copy of the altered gene is sufficient to cause the disorder. In most cases, an affected person has one parent with the condition. A small percentage of cases result from new mutations in the gene; these cases occur in people with no history of the disorder in their family. It has been suggested that this article or section be merged into Dominance relationship. ...

Some cases of type II and type IV Waardenburg syndrome appear to have an autosomal recessive pattern of inheritance, which means two copies of the gene must be altered for a person to be affected by the disorder. Most often, the parents of a child with an autosomal recessive disorder are not affected but are carriers of one copy of the altered gene. In genetics, the term recessive gene refers to an allele that causes a phenotype (visible or detectable characteristic) that is only seen in a homozygous genotype (an organism that has two copies of the same allele). ...

Waardenburg syndrome is usually inherited in an autosomal dominant pattern. Image File history File links Autodominant. ... It has been suggested that this article or section be merged into Dominance relationship. ...

Types II and IV Waardenburg syndrome may sometimes have an autosomal recessive pattern of inheritance. Wikipedia does not yet have an article with this exact name. ... In genetics, the term recessive gene refers to an allele that causes a phenotype (visible or detectable characteristic) that is only seen in a homozygous genotype (an organism that has two copies of the same allele). ...

Treatment

There is currently no treatment or cure for Waardenburg syndrome. The symptom most likely to be of practical importance is deafness, and this is treated as any other irreversible deafness would be. In marked cases there may be cosmetic issues. Other abnormalities (neurological, structural) associated with the syndrome are treated symptomatically.

In animals

Waardenburg syndrome is known to occur in ferrets. The affected animal will usually have a small white stripe along the top of its head and a somewhat, although barely noticeably, flatter skull than normal ferrets. As a ferret's sense of hearing is poor to begin with it is not easily noticeable except for when the affected animal does not react to loud noises that non-affected ones will respond to. As the disorder is easily spread to offspring, the affected animal will not be used for breeding, although it may still be neutered and sold as a pet. Trinomial name Mustela putorius furo In general use, a ferret is a Domestic Ferret (Mustela putorius furo), a creature first bred from the wild European Polecat at least 2,500 years ago. ...

External links

• OMIM Genetic disorder catalog - Waardenburg syndrome