MedGen

Prader-Willi syndrome (PWS) is characterized by severe hypotonia, poor appetite, and feeding difficulties in early infancy, followed in early childhood by excessive eating and gradual development of morbid obesity (unless food intake is strictly controlled). Motor milestones and language development are delayed. All individuals have some degree of cognitive impairment. Hypogonadism is present in both males and females and manifests as genital hypoplasia, incomplete pubertal development, and, in most, infertility. Short stature is common (if not treated with growth hormone). A distinctive behavioral phenotype (temper tantrums, stubbornness, manipulative behavior, and obsessive-compulsive characteristics) is common. Characteristic facial features, strabismus, and scoliosis are often present. [from GeneReviews]

Sotos syndrome is characterized by a distinctive facial appearance (broad, prominent forehead with a dolichocephalic head shape, sparse frontotemporal hair, downslanting palpebral fissures, malar flushing, long and narrow face, tall chin); learning disability (early developmental delay, mild-to-severe intellectual impairment); and overgrowth (height and/or head circumference =2 SD above the mean). These three clinical features (distinctive facial features, learning disability, and overgrowth) are considered the cardinal features of Sotos syndrome. Major features of Sotos syndrome include behavioral findings (most notably autism spectrum disorder), advanced bone age, cardiac anomalies, cranial MRI/CT abnormalities, joint hyperlaxity with or without pes planus, maternal preeclampsia, neonatal complications, renal anomalies, scoliosis, and seizures. [from GeneReviews]

X-linked congenital retinoschisis (XLRS) is characterized by symmetric bilateral macular involvement with onset in the first decade of life, in some cases as early as age three months. Fundus examination shows areas of schisis (splitting of the nerve fiber layer of the retina) in the macula, sometimes giving the impression of a spoke wheel pattern. Schisis of the peripheral retina, predominantly inferotemporally, occurs in approximately 50% of individuals. Affected males typically have 20/60 to 20/120 vision. Visual acuity often deteriorates during the first and second decades of life but then remains relatively stable until the fifth or sixth decade. [from GeneReviews]

Cockayne syndrome (referred to as CS in this GeneReview) spans a continuous phenotypic spectrum that includes CS type I, the "classic" or "moderate" form; CS type II, a more severe form with symptoms present at birth (this form overlaps with cerebrooculofacioskeletal [COFS] syndrome); CS type III, a milder and later-onset form; and COFS syndrome, a fetal form of CS. CS type I is characterized by normal prenatal growth with the onset of growth and developmental abnormalities in the first two years. By the time the disease has become fully manifest, height, weight, and head circumference are far below the fifth percentile. Progressive impairment of vision, hearing, and central and peripheral nervous system function leads to severe disability; death typically occurs in the first or second decade. CS type II is characterized by growth failure at birth, with little or no postnatal neurologic development. Congenital cataracts or other structural anomalies of the eye may be present. Affected children have early postnatal contractures of the spine (kyphosis, scoliosis) and joints. Death usually occurs by age five years. CS type III is a phenotype in which major clinical features associated with CS only become apparent after age two years; growth and/or cognition exceeds the expectations for CS type I. COFS syndrome is characterized by very severe prenatal developmental anomalies (arthrogryposis and microphthalmia). [from GeneReviews]

Blepharophimosis, ptosis, and epicanthus inversus syndrome (BPES) is defined by a complex eyelid malformation characterized by four major features, all present at birth: blepharophimosis, ptosis, epicanthus inversus, and telecanthus. BPES type I includes the four major features and primary ovarian insufficiency; BPES type II includes only the four major features. Other ophthalmic manifestations that can be associated with BPES include dysplastic eyelids, lacrimal duct anomalies, strabismus, refractive errors, and amblyopia. Other craniofacial features may include a broad nasal bridge and low-set ears. [from GeneReviews]

Fukuyama congenital muscular dystrophy (FCMD) is characterized by hypotonia, symmetric generalized muscle weakness, and brain malformations including, classically, cobblestone lissencephaly with cerebral and cerebellar dysplasia. There is a spectrum of severity and mild, typical, and severe phenotypes are recognized. Disease onset typically occurs in early infancy with poor suck/swallow, weak cry, and floppiness. Serum creatine kinase (CK) levels are usually in the thousands (10-60 times higher than normal). Motor development peaks at around age five to six years and thereafter regresses as muscle atrophy progresses. In the typical case, sitting without support or sliding along the floor on the buttocks may be the peak motor function. Deep tendon reflexes are diminished or absent after early infancy. Affected individuals have contractures of the hips, knees, and interphalangeal joints. Later-onset features include a myopathic facial appearance, pseudohypertrophy of the calves and forearms, motor and speech delays, intellectual disability, seizures, ophthalmologic abnormalities including visual impairment and retinal dysplasia, and progressive cardiac involvement after age ten years. Swallowing disturbance occurs in individuals with severe FCMD and in individuals older than age ten years, leading to recurrent aspiration pneumonia and death. [from GeneReviews]

Aarskog-Scott syndrome is a genetic disorder that affects the development of many parts of the body, most commonly the head and face, the hands and feet, and the genitals and urinary system (genitourinary tract). This condition mainly affects males, although females may have mild features of the syndrome.

People with Aarskog-Scott syndrome often have distinctive facial features, such as widely spaced eyes (hypertelorism), a small nose, a long area between the nose and mouth (philtrum), and a widow's peak hairline. They frequently have mild to moderate short stature during childhood, but their growth usually catches up with that of their peers during puberty. Hand abnormalities are common in this syndrome and include short fingers (brachydactyly), curved pinky fingers (fifth finger clinodactyly), webbing of the skin between some fingers (cutaneous syndactyly), and a single crease across the palm. Affected individuals can also have wide, flat feet with broad, rounded toes. Other abnormalities in people with Aarskog-Scott syndrome include heart defects and a split in the upper lip (cleft lip) with or without an opening in the roof of the mouth (cleft palate).

Most males with Aarskog-Scott syndrome have a shawl scrotum, in which the scrotum surrounds the penis instead of hanging below. Less often, they have undescended testes (cryptorchidism) or a soft out-pouching around the belly-button (umbilical hernia) or in the lower abdomen (inguinal hernia).

The intellectual development of people with Aarskog-Scott syndrome varies widely. Most individuals with Aarskog-Scott syndrome have normal intelligence; however, some may have mild learning and behavior problems, and in rare cases, severe intellectual disability has been reported. [from MedlinePlus Genetics]

The creatine deficiency disorders (CDDs), inborn errors of creatine metabolism and transport, comprise three disorders: the creatine biosynthesis disorders guanidinoacetate methyltransferase (GAMT) deficiency and L-arginine:glycine amidinotransferase (AGAT) deficiency; and creatine transporter (CRTR) deficiency. Developmental delay and cognitive dysfunction or intellectual disability and speech-language disorder are common to all three CDDs. Onset of clinical manifestations of GAMT deficiency (reported in ~130 individuals) is between ages three months and two years; in addition to developmental delays, the majority of individuals have epilepsy and develop a behavior disorder (e.g., hyperactivity, autism, or self-injurious behavior), and about 30% have movement disorder. AGAT deficiency has been reported in 16 individuals; none have had epilepsy or movement disorders. Clinical findings of CRTR deficiency in affected males (reported in ~130 individuals) in addition to developmental delays include epilepsy (variable seizure types and may be intractable) and behavior disorders (e.g., attention deficit and/or hyperactivity, autistic features, impulsivity, social anxiety), hypotonia, and (less commonly) a movement disorder. Poor weight gain with constipation and prolonged QTc on EKG have been reported. While mild-to-moderate intellectual disability is commonly observed up to age four years, the majority of adult males with CRTR deficiency have been reported to have severe intellectual disability. Females heterozygous for CRTR deficiency are typically either asymptomatic or have mild intellectual disability, although a more severe phenotype resembling the male phenotype has been reported. [from GeneReviews]

The spectrum of COL4A1-related disorders includes: small-vessel brain disease of varying severity including porencephaly, variably associated with eye defects (retinal arterial tortuosity, Axenfeld-Rieger anomaly, cataract) and systemic findings (kidney involvement, muscle cramps, cerebral aneurysms, Raynaud phenomenon, cardiac arrhythmia, and hemolytic anemia). On imaging studies, small-vessel brain disease is manifest as diffuse periventricular leukoencephalopathy, lacunar infarcts, microhemorrhage, dilated perivascular spaces, and deep intracerebral hemorrhages. Clinically, small-vessel brain disease manifests as infantile hemiparesis, seizures, single or recurrent hemorrhagic stroke, ischemic stroke, and isolated migraine with aura. Porencephaly (fluid-filled cavities in the brain detected by CT or MRI) is typically manifest as infantile hemiparesis, seizures, and intellectual disability; however, on occasion it can be an incidental finding. HANAC (hereditary angiopathy with nephropathy, aneurysms, and muscle cramps) syndrome usually associates asymptomatic small-vessel brain disease, cerebral large vessel involvement (i.e., aneurysms), and systemic findings involving the kidney, muscle, and small vessels of the eye. Two additional phenotypes include isolated retinal artery tortuosity and nonsyndromic autosomal dominant congenital cataract. [from GeneReviews]

Phosphoribosylpyrophosphate synthetase (PRS) superactivity comprises two phenotypes, both characterized by hyperuricemia and hyperuricosuria. The mild phenotype (~75% of affected males) with onset in the second or third decade of life is typically limited to these biochemical findings, whereas the severe phenotype (~25% of affected males) with onset in the first decade of life has in addition to these biochemical findings variable combinations of developmental delay (DD) / intellectual disability (ID), sensorineural hearing loss, hypotonia, and ataxia. In the mild phenotype, uric acid crystalluria or a urinary stone is commonly the first clinical finding, followed later by gouty arthritis if serum urate concentration is not controlled. [from GeneReviews]

Myhre syndrome is a multisystem progressive connective tissue disorder that often results in significant complications. The highly distinctive (and often severe) findings of joint stiffness, restrictive lung and cardiovascular disease, progressive and proliferative fibrosis, and thickening of the skin usually occur spontaneously. Some proliferation such as abnormal scarring or adhesions may follow trauma, invasive medical procedures, or surgery. Effusions of the heart, airways, lungs, uterus, and peritoneum may occur and can progress to fibrosis. Most affected individuals have characteristic facial features (short palpebral fissures, deeply set eyes, maxillary underdevelopment, short philtrum, thin vermilion of the upper lip, narrow mouth, and prognathism) and developmental delay / cognitive disability, typically in the mild-to-moderate range. Neurobehavioral issues may include autism spectrum disorder (ASD), attention-deficit/hyperactivity disorder (ADHD), and/or anxiety. Although immunoglobulin (Ig) G and IgA deficiency are rare, affected individuals can experience recurrent infections (including otitis media, sinusitis, mastoiditis, or croup). Hearing loss can progress over time. Growth may be impaired in early life. Most adolescents develop obesity. Eye findings can include refractive errors, astigmatism, corectopia, and optic nerve anomalies. Gastrointestinal (GI) issues may include gastroesophageal reflux disease, constipation, and encopresis. Less commonly, stenosis of the GI tract, Hirschsprung disease, and/or metabolic dysfunction-associated liver disease may be observed. [from GeneReviews]

Koolen-de Vries syndrome (KdVS) is characterized by congenital malformations, developmental delay / intellectual disability, neonatal/childhood hypotonia, epilepsy, dysmorphisms, and behavioral features. Psychomotor developmental delay is noted in all individuals from an early age. The majority of individuals with KdVS function in the mild-to-moderate range of intellectual disability. Other findings include speech and language delay (100%), epilepsy (~33%), congenital heart defects (25%-50%), renal and urologic anomalies (25%-50%), and cryptorchidism. Behavior in most is described as friendly, amiable, and cooperative. [from GeneReviews]

Microcephalic osteodysplastic primordial dwarfism type II (MOPDII), the most common form of microcephalic primordial dwarfism, is characterized by extreme short stature and microcephaly along with distinctive facial features. Associated features that differentiate it from other forms of primordial dwarfism and that may necessitate treatment include: abnormal dentition, a slender bone skeletal dysplasia with hip deformity and/or scoliosis, insulin resistance / diabetes mellitus, chronic kidney disease, cardiac malformations, and global vascular disease. The latter includes neurovascular disease such as moyamoya vasculopathy and intracranial aneurysms (which can lead to strokes), coronary artery disease (which can lead to premature myocardial infarctions), and renal vascular disease. Hypertension, which is also common, can have multiple underlying causes given the complex comorbidities. [from GeneReviews]

SRCAP-related Floating-Harbor syndrome (SRCAP-FHS) is characterized by typical craniofacial features; low birth weight, normal head circumference, and short stature; bone age delay that normalizes between ages six and 12 years; skeletal anomalies (brachydactyly, broad fingertips, clinodactyly, short thumbs, prominent joints, and clavicular abnormalities); severe receptive and expressive language impairment; hypernasality and high-pitched voice; and intellectual disability that is typically mild to moderate. Difficulties with temperament and behavior, present in many children, tend to improve in adulthood. Other features can include hyperopia and/or strabismus, conductive hearing loss, seizures, gastroesophageal reflux, renal anomalies (e.g., hydronephrosis / renal pelviectasis, cysts, and/or agenesis), and genital anomalies (e.g., hypospadias and/or undescended testes). [from GeneReviews]

SHORT syndrome is a mnemonic for short stature, hyperextensibility, ocular depression (deeply set eyes), Rieger anomaly, and teething delay. It is now recognized that the features most consistently observed in SHORT syndrome are mild intrauterine growth restriction (IUGR); mild to moderate short stature; partial lipodystrophy (evident in the face, and later in the chest and upper extremities, often sparing the buttocks and legs); and a characteristic facial gestalt. Insulin resistance may be evident in mid-childhood or adolescence, although diabetes mellitus typically does not develop until early adulthood. Other frequent features include Axenfeld-Rieger anomaly or related ocular anterior chamber dysgenesis, delayed dentition and other dental issues, and sensorineural hearing loss. [from GeneReviews]

The constitutional deletion of chromosome 1p36 results in a syndrome with multiple congenital anomalies and mental retardation (Shapira et al., 1997). Monosomy 1p36 is the most common terminal deletion syndrome in humans, occurring in 1 in 5,000 births (Shaffer and Lupski, 2000; Heilstedt et al., 2003). See also neurodevelopmental disorder with or without anomalies of the brain, eye, or heart (NEDBEH; 616975), which shows overlapping features and is caused by heterozygous mutation in the RERE gene (605226) on proximal chromosome 1p36. See also Radio-Tartaglia syndrome (RATARS; 619312), caused by mutation in the SPEN gene (613484) on chromosome 1p36, which shows overlapping features. [from OMIM]

Chondrodysplasia with congenital joint dislocations, CHST3-related (CDCJD-CHST3) is characterized by short stature of prenatal onset, joint dislocations (knees, hips, radial heads), clubfeet, and limitation of range of motion that can involve all large joints. Kyphosis and occasionally scoliosis with slight shortening of the trunk develop in childhood. Minor heart valve dysplasia has been described in several persons. Intellect and vision are normal. [from GeneReviews]

Hermansky-Pudlak syndrome (HPS) is characterized by oculocutaneous albinism, a bleeding diathesis, and, in some individuals, pulmonary fibrosis, granulomatous colitis, and/or immunodeficiency. Ocular findings include nystagmus, reduced iris pigment, reduced retinal pigment, foveal hypoplasia with significant reduction in visual acuity (usually in the range of 20/50 to 20/400), and strabismus in many individuals. Hair color ranges from white to brown; skin color ranges from white to olive and is usually at least a shade lighter than that of other family members. The bleeding diathesis can result in variable degrees of bruising, epistaxis, gingival bleeding, postpartum hemorrhage, colonic bleeding, and prolonged bleeding with menses or after tooth extraction, circumcision, and/or other surgeries. Pulmonary fibrosis, colitis, and/or neutropenia have been reported in individuals with pathogenic variants in some HPS-related genes. Pulmonary fibrosis, a restrictive lung disease, typically causes symptoms in the early 30s and can progress to death within a decade. Granulomatous colitis is severe in about 15% of affected individuals. Neutropenia and/or immune defects occur primarily in individuals with pathogenic variants in AP3B1 and AP3D1. [from GeneReviews]

Renpenning syndrome (RENS1) is an X-linked syndromic intellectual developmental disorder with clinically recognizable features. Affected individuals have microcephaly, short stature, small testes, and dysmorphic facies, including tall narrow face, upslanting palpebral fissures, abnormal nasal configuration, cupped ears, and short philtrum. The nose may appear long or bulbous, with overhanging columella. Less consistent manifestations include ocular colobomas, cardiac malformations, cleft palate, and anal anomalies. Stevenson et al. (2005) proposed that the various X-linked mental retardation syndromes due to PQBP1 mutations be combined under the name of Renpenning syndrome. [from OMIM]

Cockayne syndrome (referred to as CS in this GeneReview) spans a continuous phenotypic spectrum that includes CS type I, the "classic" or "moderate" form; CS type II, a more severe form with symptoms present at birth (this form overlaps with cerebrooculofacioskeletal [COFS] syndrome); CS type III, a milder and later-onset form; and COFS syndrome, a fetal form of CS. CS type I is characterized by normal prenatal growth with the onset of growth and developmental abnormalities in the first two years. By the time the disease has become fully manifest, height, weight, and head circumference are far below the fifth percentile. Progressive impairment of vision, hearing, and central and peripheral nervous system function leads to severe disability; death typically occurs in the first or second decade. CS type II is characterized by growth failure at birth, with little or no postnatal neurologic development. Congenital cataracts or other structural anomalies of the eye may be present. Affected children have early postnatal contractures of the spine (kyphosis, scoliosis) and joints. Death usually occurs by age five years. CS type III is a phenotype in which major clinical features associated with CS only become apparent after age two years; growth and/or cognition exceeds the expectations for CS type I. COFS syndrome is characterized by very severe prenatal developmental anomalies (arthrogryposis and microphthalmia). [from GeneReviews]