MedGen

46,XY gonadal dysgenesis-motor and sensory neuropathy syndrome is a rare, genetic, developmental defect during embryogenesis disorder characterized by partial (unilateral testis, persistence of Müllerian duct structures) or complete (streak gonads only) gonadal dysgenesis, usually manifesting with primary amenorrhea in individuals with female phenotype but 46,XY karyotype, and sensorimotor dysmyelinating minifascicular polyneuropathy, which presents with numbness, weakness, exercise-induced muscle cramps, sensory disturbances and reduced/absent deep tendon reflexes. Germ cell tumors (seminoma, dysgerminoma, gonadoblastoma) may develop from the gonadal tissue. [from ORDO]

Postaxial polydactyly type A7 (PAPA7) is an autosomal recessive disorder characterized by postaxial polydactyly and brachydactyly of the hands and/or feet. Features reported in some patients include syndactyly of the second and third digits of the feet, learning disabilities, and increased body weight (Umair et al., 2017; Estrada-Cuzcano et al., 2020). For a discussion of genetic heterogeneity of postaxial polydactyly, see 174200. [from OMIM]

Primary ciliary dyskinesia-33 is an autosomal recessive disorder characterized by recurrent upper and lower respiratory infections due to defective ciliary clearance and resulting in chronic lung disease. Some patients may have recurrent ear infections resulting in conductive hearing impairment. Examination of respiratory cilia shows subtle movement defects. Laterality defects have not been reported (summary by Olbrich et al., 2015). For a phenotypic description and a discussion of genetic heterogeneity of primary ciliary dyskinesia, see CILD1 (244400). [from OMIM]

Any holoprosencephaly in which the cause of the disease is a mutation in the CDON gene. [from MONDO]

Cutaneous basal cell carcinoma (BCC) is the most common cancer among people of European ancestry (Stacey et al., 2009). The primary environmental risk factor for BCC is sun exposure, but genetics also has a substantial role. Some of the sequence variants that confer susceptibility seem to operate through their association with fair-pigmentation traits common among Europeans, resulting in reduced protection from the damaging effects of ultraviolet (UV) radiation. Other sequence variants have no obvious role in pigmentation or UV susceptibility but instead seem to operate in the contexts of growth and differentiation of the basal layers of the skin (Stacey et al., 2008; Epstein, 2008; Gudbjartsson et al., 2008; Rafnar et al., 2009). See ASIP (600201), TYR (606933), and SHEP5 (227240) for examples of basal cell carcinoma associated with fair skin or sensitivity to sun. Basal cell carcinoma occurs as a feature of multiple syndromes, including basal cell nevus syndrome (BCNS; 109400), Bazex syndrome (301845), Rombo syndrome (180730), Brooke-Spiegler syndrome (605041), Muir-Torre syndrome (158320), and xeroderma pigmentosum (see 278700). Abnormalities in the Hedgehog signaling pathway are found in basal cell carcinomas; see SHH (600725) and SMOH (601500). Genetic Heterogeneity of Susceptibility to Basal Cell Carcinoma Susceptibility to basal cell carcinoma is a genetically heterogeneous trait. The BCC1 locus maps to chromosome 1p36. Also see BCC2 (613058) on 1q42; BCC3 (613059) on 5p15; BCC4 (613061) on 12q13; BCC5 (613062) on 9p21; and BCC6 (613063) on 7q32. Variation in the 3-prime untranslated region of TP53 (191170) increases susceptibility to basal cell carcinoma (BCC7; 614740). Somatic mutation contributing to the formation of basal cell carcinoma has been identified in the RASA1 (139150), PTCH1 (601309), and PTCH2 (603673) genes. [from OMIM]

Holoprosencephaly (HPE) is the most commonly occurring congenital structural forebrain anomaly in humans. HPE is associated with mental retardation and craniofacial malformations. Considerable heterogeneity in the genetic causes of HPE has been demonstrated (Ming et al., 2002). For general phenotypic information and a discussion of genetic heterogeneity of holoprosencephaly, see HPE1 (236100). [from OMIM]

Any microphthalmia, isolated, with coloboma in which the cause of the disease is a mutation in the SHH gene. [from MONDO]

Acrocapitofemoral dysplasia (ACFD) is an autosomal recessive skeletal dysplasia characterized by postnatal-onset disproportionate short stature, relatively large head, narrow thorax, lumbar lordosis, short limbs, and brachydactyly with small broad nails (Ozyavuz Cubuk and Duz, 2021). [from OMIM]

Any holoprosencephaly in which the cause of the disease is a mutation in the SHH gene. [from MONDO]

A single maxillary central incisor positioned in the midline with morphological symmetry of the crown and bordered by lateral incisors. [from HPO]

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]

Weyers acrofacial dysostosis (WAD) is an autosomal dominant disorder with dental anomalies, nail dystrophy, postaxial polydactyly, and mild short stature. Ellis-van Creveld syndrome is a similar disorder, with autosomal recessive inheritance and the additional features of disproportionate dwarfism, thoracic dysplasia, and congenital heart disease (summary by Howard et al., 1997). [from OMIM]

Pallister-Hall-like syndrome (PHLS) is a pleiotropic autosomal recessive disorder characterized by phenotypic variability. Patients exhibit postaxial polydactyly as well as hypothalamic hamartoma, cardiac and skeletal anomalies, and craniofacial dysmorphisms. Hirschsprung disease has also been observed (Rubino et al., 2018; Le et al., 2020). Pallister-Hall syndrome (146510) is an autosomal dominant disorder with features overlapping those of PHLS, caused by mutation in the GLI3 gene (165240). [from OMIM]

Brunelli et al. (1996) described schizencephaly as an extremely rare congenital disorder characterized by a full-thickness cleft within the cerebral hemispheres. The clefts are lined with gray matter and most commonly involve the parasylvian regions (Wolpert and Barnes, 1992). Large portions of the cerebral hemispheres may be absent and replaced by cerebrospinal fluid. Two types of schizencephaly have been described, depending on the size of the area involved and the separation of the cleft lips (Wolpert and Barnes, 1992). Type I schizencephaly consists of a fused cleft. This fused pial-ependymal seam forms a furrow in the developing brain, and is lined by polymicrogyric gray matter. In type II schizencephaly, there is a large defect, a holohemispheric cleft in the cerebral cortex filled with fluid and lined by polymicrogyric gray matter. The clinical manifestations depend on the severity of the lesion. Patients with type I are often almost normal; they may have seizures and spasticity. In type II abnormalities, there is usually mental retardation, seizures, hypotonia, spasticity, inability to walk or speak, and blindness. Schizencephaly may be part of the larger phenotypic spectrum of holoprosencephaly (HPE; see 236100). [from OMIM]

Ellis-van Creveld syndrome is an autosomal recessive skeletal dysplasia characterized by short limbs, short ribs, postaxial polydactyly, and dysplastic nails and teeth. Congenital cardiac defects, most commonly a defect of primary atrial septation producing a common atrium, occur in 60% of affected individuals (summary by Ruiz-Perez et al., 2000). The clinical features of the Ellis-van Creveld syndrome appear to be identical regardless of whether the disorder is caused by mutation in the EVC gene (604831) or in the EVC2 gene (607261) (Ruiz-Perez et al., 2003, Galdzicka et al., 2002). [from OMIM]