MedGen

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]

Bronchial asthma is the most common chronic disease affecting children and young adults. It is a complex genetic disorder with a heterogeneous phenotype, largely attributed to the interactions among many genes and between these genes and the environment. Asthma-related traits include clinical symptoms of asthma, such as coughing, wheezing, and dyspnea; bronchial hyperresponsiveness (BHR) as assessed by methacholine challenge test; serum IgE levels; atopy; and atopic dermatitis (Laitinen et al., 2001; Illig and Wjst, 2002; Pillai et al., 2006). See 147050 for information on the asthma-associated phenotype atopy. [from OMIM]

Xeroderma pigmentosum (XP) is characterized by: Acute sun sensitivity (severe sunburn with blistering, persistent erythema on minimal sun exposure) with marked freckle-like pigmentation of the face before age two years; Sunlight-induced ocular involvement (photophobia, severe keratitis, atrophy of the skin of the lids, ocular surface neoplasms); Greatly increased risk of sunlight-induced cutaneous neoplasms (basal cell carcinoma, squamous cell carcinoma, melanoma) within the first decade of life. Approximately 25% of affected individuals have neurologic manifestations (acquired microcephaly, diminished or absent deep tendon stretch reflexes, progressive sensorineural hearing loss, progressive cognitive impairment, and ataxia). The most common causes of death are skin cancer, neurologic degeneration, and internal cancer. The median age at death in persons with XP with neurodegeneration (29 years) was found to be younger than that in persons with XP without neurodegeneration (37 years). [from GeneReviews]

Usher syndrome type II (USH2) is characterized by the following: Congenital, bilateral sensorineural hearing loss that is mild to moderate in the low frequencies and severe to profound in the higher frequencies. Intact or variable vestibular responses. Retinitis pigmentosa (RP); progressive, bilateral, symmetric retinal degeneration that begins with night blindness and constricted visual fields (tunnel vision) and eventually includes decreased central visual acuity; the rate and degree of vision loss vary within and among families. [from GeneReviews]

Although hypertelorism means an excessive distance between any paired organs (e.g., the nipples), the use of the word has come to be confined to ocular hypertelorism. Hypertelorism occurs as an isolated feature and is also a feature of many syndromes, e.g., Opitz G syndrome (see 300000), Greig cephalopolysyndactyly (175700), and Noonan syndrome (163950) (summary by Cohen et al., 1995). [from OMIM]

Sitosterolemia is characterized by: Hypercholesterolemia (especially in children) which (1) shows an unexpected significant lowering of plasma cholesterol level in response to low-fat diet modification or to bile acid sequestrant therapy; or (2) does not respond to statin therapy; Tendon xanthomas or tuberous (i.e., planar) xanthomas that can occur in childhood and in unusual locations (heels, knees, elbows, and buttocks); Premature atherosclerosis, which can lead to angina, aortic valve involvement, myocardial infarction, and sudden death; Hemolytic anemia, abnormally shaped erythrocytes (stomatocytes), and large platelets (macrothrombocytopenia). On occasion, the abnormal hematologic findings may be the initial presentation or the only clinical feature of this disorder. Arthritis, arthralgias, and splenomegaly may sometimes be seen and one study has concluded that "idiopathic" liver disease could be undiagnosed sitosterolemia. The clinical spectrum of sitosterolemia is probably not fully appreciated due to underdiagnosis and the fact that the phenotype in infants is likely to be highly dependent on diet. [from GeneReviews]

Complex cortical dysplasia with other brain malformations-14A (CDCBM14A) is an autosomal recessive neurologic disorder characterized by global developmental delay with impaired intellectual development, motor delay, poor speech development, and early-onset seizures, often focal or atypical absence. Additional features may include strabismus, nystagmus, exo- or esotropia, axial hypotonia, and spasticity. Brain imaging shows bilateral frontoparietal polymicrogyria, a frontal-predominant cobblestone malformation of the cortex, scalloping of the cortical/white matter junction, enlarged ventricles, and hypoplasia of the pons, brainstem, and cerebellum. The disorder can be classified as a malformation of cortical development (summary by Parrini et al., 2009; Luo et al., 2011; Zulfiqar et al., 2021). For a discussion of genetic heterogeneity of CDCBM, see CDCBM1 (614039). [from OMIM]

A rare genetic neuromuscular disease characterized by proximal muscle weakness with an early involvement of foot and hand muscles following normal motor development in early childhood, a rapidly progressive disease course leading to generalized areflexic tetraplegia with contractures, severe scoliosis, hyperlordosis, and progressive respiratory insufficiency leading to assisted ventilation. Cranial nerve functions are normal and tongue wasting and fasciculations are absent. Milder phenotype with a moderate generalized weakness and slower disease progress was reported. There is evidence the disease is caused by homozygous mutation in the gene encoding pleckstrin homology domain-containing protein, family G member 5 (PLEKHG5) on chromosome 1p36. [from SNOMEDCT_US]

Complex cortical dysplasia with other brain malformations-14B (CDCBM14B) is an autosomal recessive disorder characterized by strikingly restricted polymicrogyria limited to the cortex surrounding the Sylvian fissure. Affected individuals have variable intellectual and language difficulty and seizures, but no motor disability (Bae et al., 2014). For a discussion of genetic heterogeneity of CDCBM, see CDCBM1 (614039). [from OMIM]

Any febrile seizures, familial in which the cause of the disease is a mutation in the ADGRV1 gene. [from MONDO]

Sitosterolemia, also known as phytosterolemia, is an autosomal recessive metabolic condition characterized by unrestricted intestinal absorption of both cholesterol and plant-derived cholesterol-like molecules, such as sitosterol. Patients with this disorder have very high levels of plant sterols in the plasma and develop tendon and tuberous xanthomas, accelerated atherosclerosis, and premature coronary artery disease (summary by Berge et al., 2000). For a general phenotypic description and a discussion of genetic heterogeneity of sitosterolemia, see 210250. [from OMIM]

CMTRIC is an autosomal recessive peripheral neuropathy characterized by distal sensory impairment predominantly affecting the lower limbs and resulting in walking difficulties due to muscle weakness and atrophy. The upper limbs may also be affected. Electrophysiologic studies and sural nerve biopsy show mixed features of demyelinating and axonal neuropathy. The age at onset and the severity of the disease are variable (summary by Azzedine et al., 2013). For a discussion of genetic heterogeneity of autosomal recessive intermediate CMT, see CMTRIA (608340). [from OMIM]

An abnormally decreased level of immunoglobulin G (IgG) in blood. [from HPO]

VACTERL describes a constellation of congenital anomalies, including vertebral anomalies, anal atresia, congenital cardiac disease, tracheoesophageal fistula, renal anomalies, radial dysplasia, and other limb defects; see 192350. Cases of familial VACTERL with hydrocephalus (H) have been reported with suggestion of autosomal recessive or X-linked inheritance (see 314390). Other patients thought to have VACTERL-H, including 2 unrelated infants reported by Porteous et al. (1992), had been found to have Fanconi anemia (see 227650). Porteous et al. (1992) suggested that chromosomal breakage studies should be performed in all cases of VACTERL/VACTERL-H to rule out Fanconi anemia. Alter et al. (2007) noted that a VATER phenotype had been reported in Fanconi anemia of complementation groups A (227650), C (227645), D1 (605724), E (600901), F (603467), and G (614082). X-linked VACTERL-H is also associated with mutations in the FANCB gene (300515). [from OMIM]

Gout is a common disorder resulting from tissue deposition of monosodium urate crystals as a consequence of hyperuricemia. Patients with gout experience very painful attacks caused by precipitation of urate in joints, which triggers subsequent inflammation. Elevated serum uric acid concentration is a key risk factor for gout (summary from Matsuo et al., 2009 and Woodward et al., 2011). Genetic Heterogeneity of Serum Uric Acid Concentration Quantitative Trait Loci See also UAQTL2 (see 612076), conferred by variation in the SLC2A9 gene (606142) on chromosome 4p16; UAQTL4 (612671), conferred by variation in the SLC17A3 gene (611034) on chromosome 6p22; UAQTL5 (614746), associated with a SNP on chromosome 19q13; UAQTL6 (614747), associated with a SNP on chromosome 1; and UAQTL7 (see 245450), caused by mutation in the LDHD gene (607490) on chromosome 16q23. [from OMIM]

An abnormally increased level of immunoglobulin G in blood. [from HPO]