MedGen

A facial appearance characterized by a permanently or nearly permanently opened mouth. [from HPO]

Quigley (1993) reviewed adult-onset primary open angle glaucoma, which combines a particular abnormal appearance of the optic disc (optic nerve head) with a slowly progressive loss of visual sensitivity. Many patients with glaucoma have intraocular pressures above the normal range, although this cannot be considered part of the definition of the disease, since some patients have normal intraocular pressures. Changes in the optic disc, either inherited or acquired, contribute to the development of the disorder, which leads to visual loss from increasing nerve fiber layer atrophy. Quigley et al. (1994) stated that POAG should be reviewed as a multifactorial disorder. Genetic Heterogeneity of Primary Open Angle Glaucoma Other forms of primary open angle glaucoma include GLC1A (137750), caused by mutation in the MYOC gene (601652) on chromosome 1q24; GLC1B (606689) on chromosome 2cen-q13; GLC1C (601682) on chromosome 3q21-q24; GLC1D (602429) on chromosome 8q23; GLC1F (603383), caused by mutation in the ASB10 gene (615054) on chromosome 7q36; GLC1G (609887), caused by mutation in the WDR36 gene (609669) on chromosome 5q22; GLC1H (611276), caused by mutation in the EFEMP1 gene (601548) on chromosome 2p16; GLC1I (609745) on chromosome 15q11-q13; GLC1J (608695) on chromosome 9q22; GLC1K (608696) on chromosome 20p12; GLC1L (see 137750) on chromosome 3p22-p21; GLC1M (610535) on chromosome 5q22; GLC1N (611274) on chromosome 15q22-q24; GLC1O (613100), caused by mutation in the NTF4 gene (162662) on chromosome 19q13; GLC1P (177700), caused by an approximately 300-kb duplication on chromosome 12q24, most likely involving the TBK1 gene (604834). Nail-patella syndrome (NPS; 161200), which is caused by mutation in the LMX1B gene (602575) on chromosome 9q34, has open angle glaucoma as a pleiotropic feature. Other Forms of Glaucoma For a general description and a discussion of genetic heterogeneity of congenital forms of glaucoma, see GLC3A (231300). See 606657 for a discussion of normal tension glaucoma (NTG) or normal pressure glaucoma (NPG), a subtype of POAG. See 618880 for a discussion of primary closed-angle glaucoma. [from OMIM]

Glaucoma is a group of eye disorders in which the optic nerves connecting the eyes and the brain are progressively damaged. This damage can lead to reduction in side (peripheral) vision and eventual blindness. Other signs and symptoms may include bulging eyes, excessive tearing, and abnormal sensitivity to light (photophobia). The term "early-onset glaucoma" may be used when the disorder appears before the age of 40.

In most people with glaucoma, the damage to the optic nerves is caused by increased pressure within the eyes (intraocular pressure). Intraocular pressure depends on a balance between fluid entering and leaving the eyes.

Usually glaucoma develops in older adults, in whom the risk of developing the disorder may be affected by a variety of medical conditions including high blood pressure (hypertension) and diabetes mellitus, as well as family history. The risk of early-onset glaucoma depends mainly on heredity.

Other individuals experience early onset of primary open-angle glaucoma, the most common adult form of glaucoma. If primary open-angle glaucoma develops during childhood or early adulthood, it is called juvenile open-angle glaucoma.

Structural abnormalities that impede fluid drainage in the eye increase ocular pressure. These abnormalities may be present at birth and usually become apparent during the first year of life. Such structural abnormalities may be part of a genetic disorder that affects many body systems, called a syndrome. If glaucoma appears before the age of 3 without other associated abnormalities, it is called primary congenital glaucoma. [from MedlinePlus Genetics]

The trismus-pseudocamptodactyly syndrome is a distal arthrogryposis characterized by an inability to open the mouth fully (trismus) and pseudocamptodactyly in which wrist dorsiflexion, but not volar flexion, produces involuntary flexion contracture of distal and proximal interphalangeal joints. In these patients, trismus complicates dental care, feeding during infancy, and intubation for anesthesia, and the pseudocamptodactyly impairs manual dexterity, with consequent occupational and social disability (summary by Veugelers et al., 2004). [from OMIM]

Congenital disorders of glycosylation (CDGs) are a genetically heterogeneous group of autosomal recessive disorders caused by enzymatic defects in the synthesis and processing of asparagine (N)-linked glycans or oligosaccharides on glycoproteins. These glycoconjugates play critical roles in metabolism, cell recognition and adhesion, cell migration, protease resistance, host defense, and antigenicity, among others. CDGs are divided into 2 main groups: type I CDGs (see, e.g., CDG1A, 212065) comprise defects in the assembly of the dolichol lipid-linked oligosaccharide (LLO) chain and its transfer to the nascent protein, whereas type II CDGs refer to defects in the trimming and processing of the protein-bound glycans either late in the endoplasmic reticulum or the Golgi compartments. The biochemical changes of CDGs are most readily observed in serum transferrin (TF; 190000), and the diagnosis is usually made by isoelectric focusing of this glycoprotein (reviews by Marquardt and Denecke, 2003; Grunewald et al., 2002). Genetic Heterogeneity of Congenital Disorder of Glycosylation Type II Multiple forms of CDG type II have been identified; see CDG2B (606056) through CDG2Z (620201), and CDG2AA (620454) to CDG2BB (620546). [from OMIM]

A facial appearance characterized by a permanently or nearly permanently opened mouth, in which the upper lip is tented in a way that the opened mouth has the appearance of a triangle. [from HPO]

Anterior open bite is a malocclusion characterized by a gap between the anterior teeth (incisors), that is, by a deficiency in the normal vertical overlap between antagonist incisal edges when the posterior teeth are in occlusion. [from HPO]

Cleidocranial dysplasia (CCD) spectrum disorder is a skeletal dysplasia that represents a clinical continuum ranging from classic CCD (triad of delayed closure of the cranial sutures, hypoplastic or aplastic clavicles, and dental abnormalities) to mild CCD to isolated dental anomalies without the skeletal features. Most individuals come to diagnosis because they have classic features. At birth, affected individuals typically have abnormally large, wide-open fontanelles that may remain open throughout life. Clavicular hypoplasia can result in narrow, sloping shoulders that can be opposed at the midline. Moderate short stature may be observed, with most affected individuals being shorter than their unaffected sibs. Dental anomalies may include supernumerary teeth, eruption failure of the permanent teeth, and presence of the second permanent molar with the primary dentition. Individuals with CCD spectrum disorder are at increased risk of developing recurrent sinus infections, recurrent ear infections leading to conductive hearing loss, and upper-airway obstruction. Intelligence is typically normal. [from GeneReviews]

The anterior fontanelle generally ossifies by around the 18th month of life. A persistent open anterior fontanelle is diagnosed if closure is delayed beyond this age. [from HPO]

Open angle glaucoma-1H (GLC1H) is characterized by elevated intraocular pressures (IOPs) associated with visual field and optic nerve abnormalities. In some families, affected members present mostly in the 'juvenile-onset' (JOAG) age range (between 3 and 35 to 40 years of age), whereas in other families, affected individuals present mostly in the 'adult-onset' (POAG) age range (after age 35 or 40 years). Patients with early-onset disease generally have a more severe presentation, with higher IOPs and higher likelihood of being blind in at least 1 eye (summary by Mackay et al., 2015; Collantes et al., 2022). For a general phenotypic description and a discussion of genetic heterogeneity of primary open angle glaucoma (POAG), see 137760. [from OMIM]

Underdevelopment of the operculum. [from HPO]

Any open-angle glaucoma in which the cause of the disease is a mutation in the NTF4 gene. [from MONDO]

Familial dilated cardiomyopathy is a genetic form of heart disease. It occurs when heart (cardiac) muscle becomes thin and weakened in at least one chamber of the heart, causing the open area of the chamber to become enlarged (dilated). As a result, the heart is unable to pump blood as efficiently as usual. To compensate, the heart attempts to increase the amount of blood being pumped through the heart, leading to further thinning and weakening of the cardiac muscle. Over time, this condition results in heart failure.

It usually takes many years for symptoms of familial dilated cardiomyopathy to cause health problems. They typically begin in mid-adulthood, but can occur at any time from infancy to late adulthood. Signs and symptoms of familial dilated cardiomyopathy can include an irregular heartbeat (arrhythmia), shortness of breath (dyspnea), extreme tiredness (fatigue), fainting episodes (syncope), and swelling of the legs and feet. In some cases, the first sign of the disorder is sudden cardiac death. The severity of the condition varies among affected individuals, even in members of the same family. [from MedlinePlus Genetics]

Crohn's disease is a complex, long-lasting (chronic) disorder that primarily affects the digestive system. This condition involves an abnormal immune response that causes excess inflammation. It most often affects the intestinal walls, particularly in the lower part of the small intestine (the ileum) and portions of the large intestine (the colon). However, inflammation can occur in any part of the digestive system, from the mouth to the anus. The inflamed tissues become thick and swollen, and the inner surfaces of the digestive system may develop open sores (ulcers).

Crohn's disease most commonly appears in a person's late teens or twenties, although the disease can begin at any age. Signs and symptoms tend to flare up multiple times throughout life. The most common features of this condition are persistent diarrhea, abdominal pain and cramping, loss of appetite, weight loss, and fever. Some people with Crohn's disease have blood in the stool from inflamed tissues in the intestine; over time, chronic bleeding can lead to a low number of red blood cells (anemia). In some cases, Crohn's disease can also cause inflammation affecting the joints, eyes, or skin.

Intestinal blockage is a common complication of Crohn's disease. Blockages are caused by swelling or a buildup of scar tissue in the intestinal walls. Some affected individuals also develop fistulae, which are abnormal connections between the intestine and other tissues. Fistulae occur when ulcers break through the intestinal wall and passages form between loops of the intestine or between the intestine and nearby structures (such as the bladder, vagina, or skin).

Crohn's disease is one common form of inflammatory bowel disease (IBD). Another type of IBD, ulcerative colitis, also causes chronic inflammation of the intestinal lining. Unlike Crohn's disease, which can affect any part of the digestive system, ulcerative colitis typically causes inflammation only in the colon. [from MedlinePlus Genetics]

Neural tube defects have a birth incidence of approximately 1 in 1,000 in American Caucasians and are the second most common type of birth defect after congenital heart defects. The most common NTDs are open spina bifida (myelomeningocele) and anencephaly (206500) (Detrait et al., 2005). Women with elevated plasma homocysteine, low folate, or low vitamin B12 (cobalamin) are at increased risk of having a child with a neural tube defect (O'Leary et al., 2005). Motulsky (1996) cited evidence from the Centers for Disease Control ( Anonymous, 1992) that folic acid given before and during the first 4 weeks of pregnancy can prevent 50% or more of neural tube defects. Botto et al. (1999) and Detrait et al. (2005) provided reviews of neural tube defects. De Marco et al. (2006) provided a detailed review of neurulation and the possible etiologies of neural tube defects. [from OMIM]