MedGen

Apert syndrome is characterized by the presence of multisuture craniosynostosis, midface retrusion, and syndactyly of the hands with fusion of the second through fourth nails. Almost all affected individuals have coronal craniosynostosis, and a majority also have involvement of the sagittal and lambdoid sutures. The midface in Apert syndrome is underdeveloped as well as retruded; a subset of affected individuals have cleft palate. The hand in Apert syndrome always includes fusion of the middle three digits; the thumb and fifth finger are sometimes also involved. Feeding issues, dental abnormalities, hearing loss, hyperhidrosis, and progressive synostosis of multiple bones (skull, hands, feet, carpus, tarsus, and cervical vertebrae) are also common. Multilevel airway obstruction may be present and can be due to narrowing of the nasal passages, tongue-based airway obstruction, and/or tracheal anomalies. Nonprogressive ventriculomegaly is present in a majority of individuals, with a small subset having true hydrocephalus. Most individuals with Apert syndrome have normal intelligence or mild intellectual disability; moderate-to-severe intellectual disability has been reported in some individuals. A minority of affected individuals have structural cardiac abnormalities, true gastrointestinal malformations, and anomalies of the genitourinary tract. [from GeneReviews]

Wolf-Hirschhorn syndrome is a congenital malformation syndrome characterized by pre- and postnatal growth deficiency, developmental disability of variable degree, characteristic craniofacial features ('Greek warrior helmet' appearance of the nose, high forehead, prominent glabella, hypertelorism, high-arched eyebrows, protruding eyes, epicanthal folds, short philtrum, distinct mouth with downturned corners, and micrognathia), and a seizure disorder (Battaglia et al., 2008). [from OMIM]

Classic Joubert syndrome (JS) is characterized by three primary findings: A distinctive cerebellar and brain stem malformation called the molar tooth sign (MTS). Hypotonia. Developmental delays. Often these findings are accompanied by episodic tachypnea or apnea and/or atypical eye movements. In general, the breathing abnormalities improve with age, truncal ataxia develops over time, and acquisition of gross motor milestones is delayed. Cognitive abilities are variable, ranging from severe intellectual disability to normal. Additional findings can include retinal dystrophy, renal disease, ocular colobomas, occipital encephalocele, hepatic fibrosis, polydactyly, oral hamartomas, and endocrine abnormalities. Both intra- and interfamilial variation are seen. [from GeneReviews]

GLI3-related Pallister-Hall syndrome (GLI3-PHS) is characterized by a spectrum of anomalies ranging from polydactyly, asymptomatic bifid epiglottis, and hypothalamic hamartoma at the mild end to laryngotracheal cleft with neonatal lethality at the severe end. Individuals with mild GLI3-PHS may be incorrectly diagnosed as having isolated postaxial polydactyly type A. Individuals with GLI3-PHS can have pituitary insufficiency and may die as neonates from undiagnosed and untreated adrenal insufficiency. [from GeneReviews]

Typical Greig cephalopolysyndactyly syndrome (GCPS) is characterized by macrocephaly, widely spaced eyes associated with increased interpupillary distance, preaxial polydactyly with or without postaxial polydactyly, and cutaneous syndactyly. Developmental delay, intellectual disability, or seizures appear to be uncommon manifestations (~<10%) of GCPS and may be more common in individuals with large (>300-kb) deletions that encompass GLI3. Approximately 20% of individuals with GCPS have hypoplasia or agenesis of the corpus callosum. [from GeneReviews]

Fanconi anemia (FA) is characterized by physical abnormalities, bone marrow failure, and increased risk for malignancy. Physical abnormalities, present in approximately 75% of affected individuals, include one or more of the following: short stature, abnormal skin pigmentation, skeletal malformations of the upper and/or lower limbs, microcephaly, and ophthalmic and genitourinary tract anomalies. Progressive bone marrow failure with pancytopenia typically presents in the first decade, often initially with thrombocytopenia or leukopenia. The incidence of acute myeloid leukemia is 13% by age 50 years. Solid tumors – particularly of the head and neck, skin, and genitourinary tract – are more common in individuals with FA. [from GeneReviews]

Townes-Brocks syndrome (TBS) is characterized by the triad of imperforate anus (84%), dysplastic ears (87%; overfolded superior helices and preauricular tags; frequently associated with sensorineural and/or conductive hearing impairment [65%]), and thumb malformations (89%; triphalangeal thumbs, duplication of the thumb [preaxial polydactyly], and rarely hypoplasia of the thumbs). Renal impairment (42%), including end-stage renal disease (ESRD), may occur with or without structural abnormalities (mild malrotation, ectopia, horseshoe kidney, renal hypoplasia, polycystic kidneys, vesicoutereral reflux). Congenital heart disease occurs in 25%. Foot malformations (52%; flat feet, overlapping toes) and genitourinary malformations (36%) are common. Intellectual disability occurs in approximately 10% of individuals. Rare features include iris coloboma, Duane anomaly, Arnold-Chiari malformation type 1, and growth retardation. [from GeneReviews]

The branchiooculofacial syndrome (BOFS) is characterized by: branchial (cervical or infra- or supra-auricular) skin defects that range from barely perceptible thin skin or hair patch to erythematous "hemangiomatous" lesions to large weeping erosions; ocular anomalies that can include microphthalmia, anophthalmia, coloboma, and nasolacrimal duct stenosis/atresia; and facial anomalies that can include ocular hypertelorism or telecanthus, broad nasal tip, upslanted palpebral fissures, cleft lip or prominent philtral pillars that give the appearance of a repaired cleft lip (formerly called "pseudocleft lip") with or without cleft palate, upper lip pits, and lower facial weakness (asymmetric crying face or partial 7th cranial nerve weakness). Malformed and prominent pinnae and hearing loss from inner ear and/or petrous bone anomalies are common. Intellect is usually normal. [from GeneReviews]

Short-rib thoracic dysplasia (SRTD) with or without polydactyly refers to a group of autosomal recessive skeletal ciliopathies that are characterized by a constricted thoracic cage, short ribs, shortened tubular bones, and a 'trident' appearance of the acetabular roof. SRTD encompasses Ellis-van Creveld syndrome (EVC) and the disorders previously designated as Jeune syndrome or asphyxiating thoracic dystrophy (ATD), short rib-polydactyly syndrome (SRPS), and Mainzer-Saldino syndrome (MZSDS). Polydactyly is variably present, and there is phenotypic overlap in the various forms of SRTDs, which differ by visceral malformation and metaphyseal appearance. Nonskeletal involvement can include cleft lip/palate as well as anomalies of major organs such as the brain, eye, heart, kidneys, liver, pancreas, intestines, and genitalia. Some forms of SRTD are lethal in the neonatal period due to respiratory insufficiency secondary to a severely restricted thoracic cage, whereas others are compatible with life (summary by Huber and Cormier-Daire, 2012 and Schmidts et al., 2013). There is phenotypic overlap with the cranioectodermal dysplasias (Sensenbrenner syndrome; see CED1, 218330). For a discussion of genetic heterogeneity of short-rib thoracic dysplasia, see SRTD1 (208500). [from OMIM]

Mandibulofacial dysostosis with microcephaly (MFDM) is characterized by malar and mandibular hypoplasia, microcephaly (congenital or postnatal onset), intellectual disability (mild, moderate, or severe), malformations of the external ear, and hearing loss that is typically conductive. Associated craniofacial malformations may include cleft palate, choanal atresia, zygomatic arch cleft (identified on cranial CT scan), and facial asymmetry. Other relatively common findings (present in 25%-35% of individuals) can include cardiac anomalies, thumb anomalies, esophageal atresia/tracheoesophageal fistula, short stature, spine anomalies, and epilepsy. [from GeneReviews]

Orofaciodigital syndrome type VI (OFD6), or Varadi syndrome, is a rare autosomal recessive disorder distinguished from other orofaciodigital syndromes by metacarpal abnormalities with central polydactyly and by cerebellar abnormalities, including the molar tooth sign (summary by Doss et al., 1998 and Lopez et al., 2014). [from OMIM]

Preaxial polydactyly II (PPD2) is a limb malformation in which duplication, full or partial, of the first digital ray of hands or feet results in extra digits. Triphalangeal thumb is characterized by the presence of 3 phalanges within the thumb. The extra middle phalanx may be fully formed, trapezoidal, or a small triangular 'delta' phalanx; the thumb may be opposable or nonopposable. Preaxial polydactyly and triphalangeal thumb may cosegregate, or each occur in isolation, within families with mutation in the zone of polarizing activity (ZPA) regulatory sequence (ZRS), a regulatory element for the SHH gene (600725) that is contained within intron 5 of the LMBR1 gene (Heutink et al., 1994; Furniss et al., 2008; VanderMeer et al., 2014). [from OMIM]

Hydrolethalus-1 (HLS1) is an autosomal recessive lethal malformation syndrome characterized by hydrocephaly with absent upper midline structures of the brain, micrognathia, and polydactyly. Various other features such as cleft lip or palate, club feet, anomalies of the ears, eyes, and nose, keyhole-shaped defect in the occipital bone, abnormal genitalia, and congenital heart and respiratory organ defects have also been observed in affected individuals. Affected individuals are stillborn or die shortly after birth (summary by Mee et al., 2005). Genetic Heterogeneity of Hydrolethalus Syndrome See also HLS2 (614120), caused by mutation in the KIF7 gene (611254) on chromosome 15q26. [from OMIM]

Any Meier-Gorlin syndrome in which the cause of the disease is a mutation in the CDC45 gene. [from MONDO]

Supernumerary digits located at the radial side of the hand. Polydactyly (supernumerary digits) involving the thumb occurs in many distinct forms of high variability and severity. Ranging from fleshy nubbins over varying degrees of partial duplication/splitting to completely duplicated or even triplicated thumbs or preaxial (on the radial side of the hand) supernumerary digits. [from HPO]

Verloes et al. (1992) described a rare variant of frontonasal dysplasia (see FND1, 136760), designated acromelic frontonasal dysplasia (AFND), in which similar craniofacial anomalies are associated with variable central nervous system malformations and limb defects including tibial hypoplasia/aplasia, talipes equinovarus, and preaxial polydactyly of the feet. [from OMIM]

Orofaciodigital syndrome II (OFD2), also known as Mohr syndrome, is characterized by cleft lip/palate, lobulated tongue with nodules, dental anomalies including tooth agenesis, maxillary hypoplasia, conductive hearing loss, and poly-, syn-, and brachydactyly. Mesomelic shortening of the limbs has also been observed (Mohr, 1941; Gorlin, 1982; Monroe et al., 2016). [from OMIM]

Curry-Jones syndrome (CRJS) is a multisystem disorder characterized by patchy skin lesions, polysyndactyly, diverse cerebral malformations, unicoronal craniosynostosis, iris colobomas, microphthalmia, and intestinal malrotation with myofibromas or hamartomas (summary by Twigg et al., 2016). [from OMIM]

Femoral-facial syndrome (FFS), also known as femoral hypoplasia-unusual facies syndrome (FHUFS), is a rare and sporadic multiple congenital anomaly syndrome comprising bilateral femoral hypoplasia and characteristic facial features, such as long philtrum, thin upper lip, micrognathia with or without cleft palate, upward-slanting palpebral fissures, and a short nose with broad tip. Other features, such as renal anomalies, are more variable (summary by Nowaczyk et al., 2010). [from OMIM]