MedGen

CMD2H is an autosomal recessive disorder characterized by rapidly progressive dilated cardiomyopathy and death in early infancy (Verhagen et al., 2019). For a general phenotypic description and a discussion of genetic heterogeneity of dilated cardiomyopathy, see 115200. [from OMIM]

Congenital muscular dystrophy with or without seizures (MYOS) is an autosomal recessive disorder characterized by severe muscle hypotonia apparent from birth, as well as developmental delay. Laboratory studies show increased serum creatine kinase and muscle biopsy shows nonspecific dystrophic features. Most patients develop seizures or have abnormal epileptiform findings on EEG studies; other variable findings may include feeding difficulties, nystagmus, myopathic facies, areflexia, and brain atrophy on MRI (summary by Larson et al., 2018 and Henige et al., 2021). [from OMIM]

Restrictive dermopathy is a rare genodermatosis characterized mainly by intrauterine growth retardation, tight and rigid skin with erosions, prominent superficial vasculature and epidermal hyperkeratosis, facial dysmorphism (small mouth, small pinched nose and micrognathia), sparse/absent eyelashes and eyebrows, mineralization defects of the skull, thin dysplastic clavicles, pulmonary hypoplasia, multiple joint contractures, and an early neonatal lethal course. Liveborn children usually die within the first week of life (summary by Navarro et al., 2004). For a discussion of genetic heterogeneity of restrictive dermopathy, see RSDM1 (275210). [from OMIM]

Mandibuloacral dysplasia with type A lipodystrophy (MADA) is an autosomal recessive disorder characterized by growth retardation, craniofacial anomalies with mandibular hypoplasia, skeletal abnormalities with progressive osteolysis of the distal phalanges and clavicles, and pigmentary skin changes. The lipodystrophy is characterized by a marked acral loss of fatty tissue with normal or increased fatty tissue in the neck and trunk. Some patients may show progeroid features. Metabolic complications can arise due to insulin resistance and diabetes (Young et al., 1971; Simha and Garg, 2002; summary by Garavelli et al., 2009). See also MAD type B (MADB; 608612), which is caused by mutation in the ZMPSTE24 gene (606480). [from OMIM]

Halperin-Birk syndrome (HLBKS) is an autosomal recessive neurodevelopmental disorder characterized by structural brain defects, spastic quadriplegia with multiple contractures, profound developmental delay, seizures, dysmorphism, cataract, and optic nerve atrophy. Death occurs in early childhood (Halperin et al., 2019). [from OMIM]

Progressive myoclonic epilepsy-6 (EPM6) is an autosomal recessive neurologic disorder characterized by onset of ataxia in the first years of life, followed by action myoclonus and seizures later in childhood, and loss of independent ambulation in the second decade. Cognition is not usually affected, although mild memory difficulties may occur in the third decade (summary by Corbett et al., 2011). For a discussion of genetic heterogeneity of progressive myoclonic epilepsy, see EPM1A (254800). [from OMIM]

Autosomal dominant polycystic kidney disease (ADPKD) is generally a late-onset multisystem disorder characterized by bilateral kidney cysts, liver cysts, and an increased risk of intracranial aneurysms. Other manifestations include: cysts in the pancreas, seminal vesicles, and arachnoid membrane; dilatation of the aortic root and dissection of the thoracic aorta; mitral valve prolapse; and abdominal wall hernias. Kidney manifestations include early-onset hypertension, kidney pain, and kidney insufficiency. Approximately 50% of individuals with ADPKD have end-stage kidney disease (ESKD) by age 60 years. The prevalence of liver cysts increases with age and occasionally results in clinically significant severe polycystic liver disease (PLD), most often in females. Overall, the prevalence of intracranial aneurysms is fivefold higher than in the general population and further increased in those with a positive family history of aneurysms or subarachnoid hemorrhage. There is substantial variability in the severity of kidney disease and other extra-kidney manifestations. [from GeneReviews]

WFS1 Wolfram syndrome spectrum disorder (WFS1-WSSD) is a progressive neurodegenerative disorder characterized by onset of diabetes mellitus (DM) and optic atrophy (OA) before age 16 years, and typically associated with other endocrine abnormalities, sensorineural hearing loss, and progressive neurologic abnormalities (cerebellar ataxia, peripheral neuropathy, dementia, psychiatric illness, and urinary tract atony). Although DM is mostly insulin-dependent, overall the course is milder (with lower prevalence of microvascular disease) than that seen in isolated DM. OA typically results in significantly reduced visual acuity in the first decade. Sensorineural hearing impairment ranges from congenital deafness to milder, sometimes progressive, hearing impairment. [from GeneReviews]

Autosomal dominant severe congenital neutropenia-11 (SCN11) is characterized by the onset of recurrent infections, mainly bacterial, in early childhood. Laboratory studies show severe neutropenia due to maturation arrest and impaired development of myeloid cells. Other leukocyte subsets, including B cells and NK cells, may also be subtly affected. Patients should be followed for possible renal dysfunction (Van Nieuwenhove et al., 2020). For discussion of genetic heterogeneity of severe congenital neutropenia, see SCN1 (202700). [from OMIM]

Common variable immunodeficiency-15 (CVID15) is an autosomal dominant immunologic disorder characterized by the onset of severe recurrent infections in infancy or early childhood. Laboratory studies show hypogammaglobulinemia with antibody deficiencies of IgM, IgG, and IgA due to impaired plasma cell homeostasis, although other B cell subset numbers are normal. T and NK cells are also normal. Treatment with IV Ig results in a favorable clinical response to recurrent infections (Schubert et al., 2018). For a general description and a discussion of genetic heterogeneity of common variable immunodeficiency, see CVID1 (607594). [from OMIM]

PCLD2 is an autosomal dominant disease characterized by the presence of multiple liver cysts resulting from structural changes in the biliary tree during development. Abnormal biliary structures may be present early in life, but they usually remain asymptomatic until cyst growth initiates during adulthood. In advanced stages, patients may develop massively enlarged livers, which cause a spectrum of clinical features and complications. Genetic studies suggest that an accumulation of somatic hits in cyst epithelium determines the rate of cyst formation. A subset of patients (28-35%) may develop kidney cysts that are usually incidental findings and do not result in clinically significant renal disease (review by Cnossen and Drenth, 2014). For a discussion of genetic heterogeneity of polycystic liver disease, see PCLD1 (174050). [from OMIM]

Autosomal dominant tubulointerstitial kidney disease-5 (ADTKD5) is characterized by the onset of progressive chronic renal disease in the first decades of life. Mild hyperuricemia may be present, but gout, hypertension, and proteinuria are usually absent. The disease may be associated with anemia or neutropenia. Some patients may have additional findings, including poor overall growth and impaired cognitive function. Renal biopsy shows tubulointerstitial abnormalities with atrophic tubules and fibrosis; secondary glomerular abnormalities and simple cysts may also be present (summary by Bolar et al., 2016). For a discussion of genetic heterogeneity and revised nomenclature of ADTKD, see ADTKD1 (162000). [from OMIM]

Combined cerebellar and peripheral ataxia with hearing loss and diabetes mellitus (ACPHD) is an autosomal recessive multisystem disorder including defects in glucose metabolism, diffuse neurodegeneration, multiple hormone deficiencies, severe growth retardation with possible growth hormone deficiencies, and subtle osseous changes suggesting early-onset bone dysplasia (summary by Ozon et al., 2020). [from OMIM]

Deficiency of very long-chain acyl-coenzyme A dehydrogenase (VLCAD), which catalyzes the initial step of mitochondrial beta-oxidation of long-chain fatty acids with a chain length of 14 to 20 carbons, is associated with three phenotypes. The severe early-onset cardiac and multiorgan failure form typically presents in the first months of life with hypertrophic or dilated cardiomyopathy, pericardial effusion, and arrhythmias, as well as hypotonia, hepatomegaly, and intermittent hypoglycemia. The hepatic or hypoketotic hypoglycemic form typically presents during early childhood with hypoketotic hypoglycemia and hepatomegaly, but without cardiomyopathy. The later-onset episodic myopathic form presents with intermittent rhabdomyolysis provoked by exercise, muscle cramps and/or pain, and/or exercise intolerance. Hypoglycemia typically is not present at the time of symptoms. [from GeneReviews]

Cataract is an opacification of the lens or lens capsule in the eye and is the most common cause of childhood blindness in the world, with an incidence of 1 to 3 per 10,000 live births. If untreated in infancy or childhood, it frequently causes visual impairment and can result in irreversible amblyopia. Nuclear cataract refers to opacification within the embryonal and/or fetal nuclei of the lens (summary by Berry et al., 2013). [from OMIM]

Congenital myasthenic syndrome-12 is an autosomal recessive neuromuscular disorder characterized by onset of proximal muscle weakness in the first decade. EMG classically shows a decremental response to repeated nerve stimulation. Affected individuals show a favorable response to acetylcholinesterase (AChE) inhibitors (summary by Senderek et al., 2011). For a discussion of genetic heterogeneity of CMS, see CMS1A (601462). [from OMIM]

FKBP14 kyphoscoliotic Ehlers-Danlos syndrome (FKBP14-kEDS) is characterized by congenital muscle hypotonia and weakness (typically improving during childhood), progressive scoliosis, joint hypermobility, hyperelastic skin, gross motor developmental delay, myopathy, and hearing impairment. Most affected children achieve independent walking between ages two and four years. A decline of motor function in adulthood may be seen, but affected individuals are likely to be able to participate in activities of daily living in adulthood and maintain independent walking. Occasional features underlying systemic connective tissue involvement include aortic rupture and arterial dissection, subdural hygroma, insufficiency of cardiac valves, bluish sclerae, bladder diverticula, inguinal or umbilical herniae, and premature rupture of membranes during pregnancy. Rarer findings may include bifid uvula with submucous or frank cleft palate, speech/language delay without true cognitive impairment, and rectal prolapse. [from GeneReviews]

Autosomal dominant Wolfram-like syndrome (WFSL) is characterized by the clinical triad of congenital progressive hearing impairment, diabetes mellitus, and optic atrophy. The hearing impairment, which is usually diagnosed in the first decade of life, is relatively constant and alters mainly low- and middle-frequency ranges (summary by Valero et al., 2008). Wolfram syndrome (WFS1; 222300) is an autosomal recessive allelic disorder characterized by optic atrophy, diabetes mellitus, hearing loss, and diabetes insipidus, and is caused by homozygous or compound heterozygous mutation in the WFS1 gene. An autosomal dominant syndrome involving optic atrophy with or without deafness, ophthalmoplegia, myopathy, ataxia, and neuropathy (125250), is caused by heterozygous mutation in the OPA1 gene (605290). [from OMIM]

Warsaw syndrome is characterized by the clinical triad of severe congenital microcephaly, growth restriction, and sensorineural hearing loss due to cochlear hypoplasia. Intellectual disability is typically in the mild-to-moderate range. Severe speech delay is common. Gross and fine motor milestones are usually attained at the usual time, although a few individuals have mild delays. Additional common features include skeletal anomalies and cardiovascular anomalies. Abnormal skin pigmentation and genitourinary malformations have also been reported. Some individuals have had increased chromosome breakage and radial forms on cytogenetic testing of lymphocytes treated with diepoxybutane and mitomycin C. [from GeneReviews]