O | Genetic and Rare Diseases Information Center (GARD) – an NCATS Program

Browse A-Z | Genetic and Rare Diseases Information Center (GARD) – an NCATS Program

• O Donnell Pappas syndrome
• OA1 - See Ocular albinism type 1
• OAFNS - See Oculoauriculofrontonasal syndrome
• OAK - See Optic atrophy 1
• OASD - See Albinism ocular late onset sensorineural deafness
• Oat cell lung cancer - See Small cell lung cancer
• OAT deficiency - See Gyrate atrophy of choroid and retina
• OAV dysplasia - See Goldenhar disease
• OAVD - See Oculo-auriculo-vertebral spectrum
• OAVS - See Goldenhar disease
• OAVS with radial defect - See Microsomia hemifacial radial defects
• Obesity due to congenital leptin deficiency
• Obesity due to congenital leptin deficiency - See Obesity due to congenital leptin deficiency
• Obesity due to pro-opiomelanocortin deficiency - See Proopiomelanocortin deficiency
• Obesity, early-onset, adrenal insufficiency, and red hair - See Proopiomelanocortin deficiency
• Obesity, mental retardation, body asymmetry, and muscle weakness - See Camera Marugo Cohen syndrome
• Obesity, morbid, nonsyndromic 1 - See Obesity due to congenital leptin deficiency
• Oblique facial clefts - See Oculomaxillofacial dysostosis
• Obliterative bronchiolitis - See Bronchiolitis obliterans
• OBSOLETE: Behr syndrome - See Behr syndrome
• OBSOLETE: Benign essential blepharospasm - See Benign essential blepharospasm
• OBSOLETE: Corpus callosum agenesis-double urinary collecting system-trigonocephaly syndrome - See Corpus callosum agenesis double urinary collecting
• OBSOLETE: Envenomization by Bothrops lanceolatus - See Envenomization by bothrops lanceolatus
• OBSOLETE: Hereditary motor and sensory neuropathy - Another name for Hereditary motor and sensory neuropathy
• OBSOLETE: Hirsutism-skeletal dysplasia-intellectual disability syndrome - See Wiedemann Oldigs Oppermann syndrome
• OBSOLETE: Preaxial polydactyly of fingers - See Polydactyly
• OBSOLETE: Shoulder and girdle defects-familial intellectual disability syndrome - See Shoulder girdle defect mental retardation familial
• Obstructive disease of the pulmonary veins - See Pulmonary venoocclusive disease
• OCA - See Oculocutaneous albinism
• OCA1 - See Oculocutaneous albinism type 1
• OCA1A - See Oculocutaneous albinism type 1
• OCA1B - See Oculocutaneous albinism type 1B
• OCA2 - See Oculocutaneous albinism type 2
• OCA3 - See Oculocutaneous albinism type 3
• OCC Syndrome - See Oculocerebrocutaneous syndrome
• Occipital atretic cephalocele, unusual facies and large feet - See Zechi Ceide syndrome
• Occipital horn syndrome
• Occlusive infantile arteriopathy - See Arterial calcification of infancy
• Occlusive peripheral vascular disease - See Buerger disease
• OCCS - See Oculocerebrocutaneous syndrome
• Occult spina bifida - See Spina bifida occulta - not a rare disease
• Occult spinal dysraphism - See Tethered cord syndrome
• Occult spinal dysraphism sequence - See Tethered cord syndrome
• Ochoa syndrome
• Ochronosis
• Ochronosis, acquired - See Exogenous ochronosis
• Ochronosis, hereditary - See Alkaptonuria
• OCRL - See Lowe oculocerebrorenal syndrome
• OCRL1 - See Lowe oculocerebrorenal syndrome
• OCTD - See MASS phenotype
• Ocular albinism type 1
• Ocular albinism with sensorineural deafness - See Albinism ocular late onset sensorineural deafness
• Ocular cicatricial pemphigoid
• Ocular colobomas, ichthyosis, brain malformations and endocrine abnormalities
• Ocular hypotelorism, submucosal cleft palate, and hypospadias - See Hypotelorism cleft palate hypospadias
• Ocular MD - See Ocular Muscular Dystrophy
• Ocular melanoma
• Ocular Muscular Dystrophy
• Ocular neuromyotonia
• Ocular Neuropathic Pain Syndrome - See Corneal neuropathic disease
• Ocular nonnephropathic cystinosis - See Cystinosis, ocular nonnephropathic
• Ocular toxoplasmosis
• Ocular-scoliotic EDS - See Kyphoscoliotic Ehlers-Danlos syndrome
• Oculo digital syndrome
• Oculo skeletal renal syndrome
• Oculoauriculofrontonasal dysplasia - See Oculoauriculofrontonasal syndrome
• Oculoauriculofrontonasal syndrome
• Oculoauriculovertebral dysplasia - See Goldenhar disease
• Oculo-Auriculo-Vertebral Dysplasia - See Oculo-auriculo-vertebral spectrum
• Oculo-auriculo-vertebral spectrum
• Oculoauriculovertebral spectrum with radial defect - See Microsomia hemifacial radial defects
• Oculoauriculovertebral syndrome - See Goldenhar disease
• Oculo-cerebral dysplasia
• Oculocerebral hypopigmentation syndrome - See Oculocerebral syndrome with hypopigmentation
• Oculocerebral hypopigmentation syndrome type Preus
• Oculocerebral syndrome with hypopigmentation
• Oculocerebrocutaneous syndrome
• Oculo-cerebro-cutaneous syndrome - See Oculocerebrocutaneous syndrome
• Oculocerebrorenal syndrome - See Lowe oculocerebrorenal syndrome
• Oculocraniosomatic syndrome - See Kearns-Sayre syndrome
• Oculocutaneous albinism
• Oculocutaneous albinism type 1
• Oculocutaneous albinism type 1A - See Oculocutaneous albinism type 1
• Oculocutaneous albinism type 1B
• Oculocutaneous albinism type 2
• Oculocutaneous albinism type 3
• Oculocutaneous albinism tyrosinase positive - See Oculocutaneous albinism type 2
• Oculocutaneous albinism, immunodeficiency, hematological disorders, and minor anomalies - See Kotzot-Richter syndrome
• Oculocutaneous albinism, minimal pigment type - See Albinism, minimal pigment type
• Oculocutaneous albinism, tyrosinase negative - See Oculocutaneous albinism type 1
• Oculocutaneous tyrosinemia - See Tyrosinemia type 2
• Oculodentodigital dysplasia
• Oculo-dento-digital dysplasia - See Oculodentodigital dysplasia
• Oculodentodigital dysplasia dominant
• Oculodentodigital syndrome - See Oculodentodigital dysplasia
• Oculo-dento-digital syndrome - See Oculodentodigital dysplasia
• Oculodentoosseous dysplasia recessive
• Oculodigitoesophagoduodenal syndrome - See Feingold syndrome
• Oculoectodermal syndrome
• Oculo-ectodermal syndrome - See Oculoectodermal syndrome
• Oculofaciocardiodental syndrome
• Oculogastrointestinal muscular dystrophy - See Mitochondrial neurogastrointestinal encephalopathy syndrome
• Oculogastrointestinal muscular dystrophy - See Familial visceral myopathy with external ophthalmoplegia
• Oculomandibulofacial syndrome - See Hallermann-Streiff syndrome
• Oculomaxillofacial dysostosis
• Oculomaxillofacial dysplasia with oblique facial clefts - See Oculomaxillofacial dysostosis
• Oculomelic amyoplasia - See Distal arthrogryposis type 5
• Oculomotor apraxia Cogan type
• Oculootoradial syndrome - See IVIC syndrome
• Oculopharyngeal distal myopathy - See Oculopharyngodistal myopathy
• Oculopharyngeal muscular dystrophy
• Oculopharyngodistal myopathy
• Oculorenocerebellar syndrome
• Oculosympathetic Palsy - See Horner's syndrome
• Oculotrichoanal syndrome - See Manitoba oculotrichoanal syndrome
• ODCD - See Spondylometaphyseal dysplasia with dentinogenesis imperfecta
• ODD syndrome - See Oculodentodigital dysplasia
• ODDD - See Oculodentodigital dysplasia
• ODED syndrome - See Feingold syndrome
• ODOD recessive - See Oculodentoosseous dysplasia recessive
• O'Doherty syndrome - See Ermine phenotype
• Odonto onycho dysplasia with alopecia
• Odontochondrodysplasia - See Spondylometaphyseal dysplasia with dentinogenesis imperfecta
• Odontogenic myxoma
• Odontoma
• Odontoma dysphagia syndrome
• Odontomatosis (multiple odontomas) with dysphagia - See Odontoma dysphagia syndrome
• Odontomicronychial dysplasia
• Odonto-micronychial dysplasia - See Odontomicronychial dysplasia
• Odontoonychodermal dysplasia
• Odontotrichomelic hypohidrotic dysplasia - See Odontotrichomelic syndrome
• Odontotrichomelic syndrome
• OEIS complex - See Omphalocele, exstrophy of the cloaca, imperforate anus, and spinal defects complex
• OFCD syndrome - See Oculofaciocardiodental syndrome
• OFD - See Orofaciodigital syndromes
• OFD syndrome 1 - See Orofaciodigital syndrome 1
• OFD syndrome 10 - See Orofaciodigital syndrome 10
• OFD syndrome 11 - See Orofaciodigital syndrome 11
• OFD syndrome 13 - See Orofaciodigital syndrome 13
• OFD syndrome 2 - See Orofaciodigital syndrome 2
• OFD syndrome 3 - See Orofaciodigital syndrome 3
• OFD syndrome 4 - See Orofaciodigital syndrome 4
• OFD syndrome 5 - See Orofaciodigital syndrome 5
• OFD syndrome 8 - See Orofaciodigital syndrome 8
• OFD syndrome 9 - See Orofaciodigital syndrome 9
• OFD syndrome with tibial defects - See Orofaciodigital syndrome 4
• OFD1 - See Orofaciodigital syndrome 1
• OFD10 - See Orofaciodigital syndrome 10
• OFD11 - See Orofaciodigital syndrome 11
• OFD12 - See Orofaciodigital syndrome 12
• OFD13 - See Orofaciodigital syndrome 13
• OFD14 - See Orofaciodigital syndrome 14
• OFD2 - See Orofaciodigital syndrome 2
• OFD3 - See Orofaciodigital syndrome 3
• OFD4 - See Orofaciodigital syndrome 4
• OFD5 - See Orofaciodigital syndrome 5
• OFD6 - See Orofaciodigital syndrome 6
• OFD8 - See Orofaciodigital syndrome 8
• OFD9 - See Orofaciodigital syndrome 9
• OFDS 1 - See Orofaciodigital syndrome 1
• OFDS 10 - See Orofaciodigital syndrome 10
• OFDS 11 - See Orofaciodigital syndrome 11
• OFDS 12 - See Orofaciodigital syndrome 12
• OFDS 13 - See Orofaciodigital syndrome 13
• OFDS 2 - See Orofaciodigital syndrome 2
• OFDS 3 - See Orofaciodigital syndrome 3
• OFDS 4 - See Orofaciodigital syndrome 4
• OFDS 5 - See Orofaciodigital syndrome 5
• OFDS 8 - See Orofaciodigital syndrome 8
• OFDS 9 - See Orofaciodigital syndrome 9
• Ofuji disease - See Eosinophilic pustular folliculitis
• Ofuji's disease - See Eosinophilic pustular folliculitis
• OGD - See Osteoglophonic dysplasia
• Ogilvie syndrome
• Ogilvie's syndrome - See Ogilvie syndrome
• OGIMD - See Mitochondrial neurogastrointestinal encephalopathy syndrome
• Oguchi disease
• OHAHA syndrome - See Infantile onset spinocerebellar ataxia
• Ohara disease - See Tularemia
• Ohdo Blepharophimosis syndrome - See Blepharophimosis intellectual disability syndromes
• Ohdo syndrome - See Blepharophimosis intellectual disability syndromes
• OHF - See Omsk hemorrhagic fever
• OHS - See Occipital horn syndrome
• OI - See Osteogenesis imperfecta
• OI 9 - See Osteogenesis imperfecta type IX
• OI type 1 - See Osteogenesis imperfecta type I
• OI type 10 - See Osteogenesis imperfecta
• OI type 11 - See Osteogenesis imperfecta
• OI type 2 - See Osteogenesis imperfecta type II
• OI type 3 - See Osteogenesis imperfecta type III
• OI type 4 - See Osteogenesis imperfecta type IV
• OI type 5 - See Osteogenesis imperfecta type V
• OI type 6 - See Osteogenesis imperfecta type VI
• OI type 7 - See Osteogenesis imperfecta type VII
• OI type III - See Osteogenesis imperfecta type III
• OI type IV - See Osteogenesis imperfecta type IV
• Oi type IX - See Osteogenesis imperfecta type IX
• OI type V - See Osteogenesis imperfecta type V
• OI type VI - See Osteogenesis imperfecta type VI
• OI type VII - See Osteogenesis imperfecta type VII
• OI type VIII - See Osteogenesis imperfecta type VIII
• OI type X - See Osteogenesis imperfecta
• OI type XI - See Osteogenesis imperfecta
• OI with calcification in interosseous membranes - See Osteogenesis imperfecta type V
• OI11 - See Osteogenesis imperfecta
• OI6 - See Osteogenesis imperfecta type VI
• OI8 - See Osteogenesis imperfecta type VIII
• Okamoto syndrome
• Okihiro syndrome - See Duane-radial ray syndrome
• OKT deficiency - See Gyrate atrophy of choroid and retina
• Old Age Pemphigus - See Bullous pemphigoid
• Olfacto-genital pathological sequence - See Kallmann syndrome
• Olfactory neuroblastoma
• Oligoarthritis, juvenile - See Pauciarticular onset juvenile idiopathic arthritis
• Oligoarticular onset juvenile idiopathic arthritis - See Pauciarticular onset juvenile idiopathic arthritis
• Oligoastrocytoma
• Oligodactyly tetramelic postaxial
• Oligodendroglioma
• Oligohydramnios sequence - See Potter sequence
• Oligomeganephronia - See Oligomeganephronic renal hypoplasia
• Oligomeganephronic renal hypoplasia
• Oligophrenia phenylpyruvica - See Phenylketonuria
• Oligophrenin-1 syndrome - See OPHN1 syndrome
• Oliver McFarlane syndrome - See Trichomegaly with intellectual disability, dwarfism and pigmentary degeneration of retina
• Oliver syndrome
• Olivopontocerebellar atrophy
• Olivopontocerebellar atrophy 1 - See Spinocerebellar ataxia 1
• Olivopontocerebellar atrophy 2 - See Spinocerebellar ataxia 2
• Olivopontocerebellar atrophy 3 - See Spinocerebellar ataxia 7
• Olivopontocerebellar atrophy 4 - See Spinocerebellar ataxia 1
• Olivopontocerebellar atrophy deafness
• Olivopontocerebellar atrophy Holguin type - See Spinocerebellar ataxia 2
• Olivopontocerebellar hypoplasia fetal-onset - See Pontocerebellar hypoplasia type 5
• Ollier disease
• Olmsted syndrome
• OMA syndrome - See Opsoclonus-myoclonus syndrome
• Omenn syndrome
• OMM syndrome - See Pillay syndrome
• OMOD1 - See Omodysplasia 1
• OMOD2 - See Omodysplasia 2
• Omodysplasia 1
• Omodysplasia 2
• Omodysplasia autosomal recessive - See Omodysplasia 1
• Omodysplasia generalized form - See Omodysplasia 1
• Omodysplasia, autosomal dominant - See Omodysplasia 2
• Omphalocele - cloacal exstrophy - imperforate anus - spinal defect - See Omphalocele, exstrophy of the cloaca, imperforate anus, and spinal defects complex
• Omphalocele cleft palate syndrome lethal
• Omphalocele syndrome, Shprintzen-Goldberg type - See Shprintzen omphalocele syndrome
• Omphalocele with hypoplasia of pharynx and larynx, learning disability, dysmorphic facies, and scoliosis - SeeShprintzen omphalocele syndrome
• Omphalocele, diaphragmatic hernia, and radial ray defects - See Gershoni-Baruch syndrome
• Omphalocele, exstrophy of the cloaca, imperforate anus, and spinal defects - See Omphalocele, exstrophy of the cloaca, imperforate anus, and spinal defects complex
• Omphalocele, exstrophy of the cloaca, imperforate anus, and spinal defects complex
• Omphalocele, laryngeal and pharyngeal hypoplasia, learning disabilities, dysmorphic facies and spinal anomalies - SeeShprintzen omphalocele syndrome
• Omphalocele-cloacal exstrophy-imperforate anus-spinal defect syndrome - See Omphalocele, exstrophy of the cloaca, imperforate anus, and spinal defects complex
• Omphalomesenteric cyst
• OMS - See Opsoclonus-myoclonus syndrome
• Omsk hemorrhagic fever
• Onat syndrome - See Subaortic stenosis short stature syndrome
• Onchocerciasis
• Oncocytic cardiomyopathy - See Infantile histiocytoid cardiomyopathy
• Oncocytoma kidney - See Renal oncocytoma
• Oncocytoma renal - See Renal oncocytoma
• Oncogenic hypophosphatemic osteomalacia - See Oncogenic osteomalacia
• Oncogenic osteomalacia
• Ondine curse (formerly) - See Congenital central hypoventilation syndrome
• Ondine's curse (formerly) - See Congenital central hypoventilation syndrome
• Onion whorl disease - See Localized hypertrophic neuropathy
• Onset of senility in the early teens, atrophic skin, hypogonadism, retinal and vascular sclerosis - See Ruvalcaba Churesigaew Myhre syndrome
• Onychocytic matricoma
• Onychodystrophy totalis - See Twenty-nail dystrophy
• Onychodystrophy-anonychia
• Onychoosteodysplasia - See Nail-patella syndrome
• Onychotrichodysplasia and neutropenia
• OOCH - See Osteoporosis oculocutaneous hypopigmentation syndrome
• OOCH syndrome - See Osteoporosis oculocutaneous hypopigmentation syndrome
• OORS - See IVIC syndrome
• OPA1 - See Optic atrophy 1
• OPA2 - See Optic atrophy 2
• OPA3 - See Autosomal dominant optic atrophy and cataract
• OPA3 defect
• OPA3, autosomal dominant - See Autosomal dominant optic atrophy and cataract
• OPA6 - See Optic atrophy 6
• OPCA - See Olivopontocerebellar atrophy
• OPCA III - See Spinocerebellar ataxia 7
• OPCA with macular degeneration and external ophthalmoplegia - See Spinocerebellar ataxia 7
• OPCA with retinal degeneration - See Spinocerebellar ataxia 7
• OPCA1 - See Spinocerebellar ataxia 1
• OPCA3 - See Spinocerebellar ataxia 7
• OPCA4 - See Spinocerebellar ataxia 1
• OPD 2 syndrome - See Oto-palato-digital syndrome type 2
• OPD syndrome - See Oto-palato-digital syndrome type 1
• OPD syndrome 1 - See Oto-palato-digital syndrome type 1
• OPD1 - See Oto-palato-digital syndrome type 1
• OPDM - See Oculopharyngodistal myopathy
• Open spine - See Spina bifida
• OPHN1 Deficiency - See OPHN1 syndrome
• OPHN1- related XLID - See OPHN1 syndrome
• OPHN1 syndrome
• OPHN1 XLMR - See OPHN1 syndrome
• OPHN1 XLMR, X-linked intellectual disability - See OPHN1 syndrome
• Ophthalmoacromelic syndrome - See Anophthalmos with limb anomalies
• Ophthalmo-mandibulo-melic dysplasia - See Pillay syndrome
• Ophthalmoplegia - hypotonia - ataxia - hypoacusis - athetosis - See Infantile onset spinocerebellar ataxia
• Ophthalmoplegia plus syndrome - See Kearns-Sayre syndrome
• Ophthalmoplegia, hypotonia, ataxia, hypacusis, and athetosis - See Infantile onset spinocerebellar ataxia
• Ophthalmoplegia, pigmentary degeneration of retina, and cardiomyopathy - See Kearns-Sayre syndrome
• Ophthalmoplegia, progressive external, with ragged red fibers - See Kearns-Sayre syndrome
• Ophthalmoplegia-hypotonia-ataxia-hypoacusis-athetosis syndrome - See Infantile onset spinocerebellar ataxia
• Ophthalmoplegia-intellectual disability-lingua scrotalis syndrome - See Levic Stefanovic Nikolic syndrome
• Ophthalmoplegic MD - See Ophthalmoplegic Muscular dystrophy
• Ophthalmoplegic Muscular dystrophy
• Opisthorchiasis
• Opitz BBBG syndrome - See Opitz G/BBB syndrome
• Opitz G/BBB syndrome
• Opitz Mollica Sorge syndrome - See Acrofacial dysostosis Catania type
• Opitz trigonocephaly syndrome - See C syndrome
• Opitz trigonocephaly-like syndrome - See Bohring-Opitz syndrome
• Opitz-Frias syndrome - See Opitz G/BBB syndrome
• Opitz-G syndrome, type 2 - See Opitz G/BBB syndrome
• Opitz-Kaveggia syndrome - See FG syndrome
• OPLL - See Ossification of the posterior longitudinal ligament of the spine - not a rare disease
• OPMD - See Oculopharyngeal muscular dystrophy
• Oppenheim disease - See Amyotonia congenita
• Oppenheim's disease - See Amyotonia congenita
• Oppenheim's dystonia - See DYT-TOR1A
• OPPG - See Osteoporosis-pseudoglioma syndrome
• OPS - See Osteoporosis-pseudoglioma syndrome
• Opsismodysplasia
• Opsoclonus myoclonus syndrome - See Opsoclonus-myoclonus syndrome
• Opsoclonus-myoclonus syndrome
• Opsoclonus-myoclonus-ataxia syndrome - See Opsoclonus-myoclonus syndrome
• OPTA1 - See Osteopetrosis autosomal dominant type 1
• OPTA2 - See Osteopetrosis autosomal dominant type 2
• OPTB1 - See Osteopetrosis autosomal recessive 1
• OPTB2 - See Osteopetrosis autosomal recessive 2
• OPTB3 - See Osteopetrosis autosomal recessive 3
• OPTB4 - See Osteopetrosis autosomal recessive 4
• OPTB5 - See Osteopetrosis autosomal recessive 5
• OPTB6 - See Osteopetrosis autosomal recessive 6
• OPTB7 - See Osteopetrosis autosomal recessive 7
• Opthalmomandibulomelic dysplasia
• Optic atrophy - deafness- polyneuropathy - myopathy - See Autosomal dominant optic atrophy plus syndrome
• Optic atrophy 1
• Optic atrophy 1 and deafness
• Optic atrophy 2
• Optic atrophy 3 - See OPA3 defect
• Optic atrophy 3 - See Autosomal dominant optic atrophy and cataract
• Optic atrophy 3 with cataract - See Autosomal dominant optic atrophy and cataract
• Optic atrophy 5
• Optic atrophy 6
• Optic atrophy in early childhood, associated with ataxia, spasticity, mental retardation, and posterior column sensory loss - See Behr syndrome
• Optic atrophy infantile with chorea and spastic paraplegia - See OPA3 defect
• Optic atrophy plus syndrome - See OPA3 defect
• Optic atrophy polyneuropathy deafness
• Optic atrophy type 1 - See Optic atrophy 1
• OPTIC ATROPHY WITH OR WITHOUT DEAFNESS, OPHTHALMOPLEGIA, MYOPATHY, ATAXIA, AND NEUROPATHY - SeeAutosomal dominant optic atrophy plus syndrome
• Optic atrophy, cataract, and neurologic disorder - See Autosomal dominant optic atrophy and cataract
• Optic atrophy, congenital or early infantile, autosomal recessive - See Optic atrophy 6
• Optic atrophy, hearing loss, and peripheral neuropathy, autosomal recessive - See Optic atrophy polyneuropathy deafness
• Optic atrophy, infantile hereditary, Behr complicated form of - See Behr syndrome
• Optic atrophy, juvenile - See Optic atrophy 1
• Optic atrophy, Kjer type - See Optic atrophy 1
• Optic atrophy, Leber type - See Leber hereditary optic neuropathy
• Optic atrophy, neural deafness, and distal neurogenic amyotrophy - See Optic atrophy polyneuropathy deafness
• Optic atrophy, non-Leber type, with early onset - See Optic atrophy 2
• Optic atrophy, polyneuropathy, and deafness - See Charcot-Marie-Tooth disease
• Optic atrophy, sensorineural hearing loss and polyneuropathy - See Charcot-Marie-Tooth disease
• Optic atrophy, X-linked - See Optic atrophy 2
• Optic atrophy-deafness-polyneuropathy-myopathy syndrome - See Autosomal dominant optic atrophy plus syndrome
• Optic coloboma, vesicoureteral reflux, and renal anomalies - See Renal coloboma syndrome
• Optic nerve coloboma - See Coloboma of optic nerve
• Optic nerve coloboma with renal disease - See Renal coloboma syndrome
• Optic nerve head pits, bilateral congenital - See Coloboma of optic nerve
• Optic nerve hypoplasia, familial bilateral
• Optic neuritis
• Optic pathway glioma
• Oral and digital anomalies with ichthyosis - See Ichthyosis tapered fingers midline groove up
• Oral cancer
• Oral facial digital syndrome 1 - See Orofaciodigital syndrome 1
• Oral facial digital syndrome 10 - See Orofaciodigital syndrome 10
• Oral facial digital syndrome 11 - See Orofaciodigital syndrome 11
• Oral facial digital syndrome 12 - See Orofaciodigital syndrome 12
• Oral facial digital syndrome 13 - See Orofaciodigital syndrome 13
• Oral facial digital syndrome 2 - See Orofaciodigital syndrome 2
• Oral facial digital syndrome 3 - See Orofaciodigital syndrome 3
• Oral facial digital syndrome 4 - See Orofaciodigital syndrome 4
• Oral facial digital syndrome 5 - See Orofaciodigital syndrome 5
• Oral facial digital syndrome 8 - See Orofaciodigital syndrome 8
• Oral facial digital syndrome 9 - See Orofaciodigital syndrome 9
• Oral facial digital syndrome type 1 - See Orofaciodigital syndrome 1
• Oral facial digital syndrome type 10 - See Orofaciodigital syndrome 10
• Oral facial digital syndrome type 11 - See Orofaciodigital syndrome 11
• Oral facial digital syndrome type 12 - See Orofaciodigital syndrome 12
• Oral facial digital syndrome type 13 - See Orofaciodigital syndrome 13
• Oral facial digital syndrome type 2 - See Orofaciodigital syndrome 2
• Oral facial digital syndrome type 3 - See Orofaciodigital syndrome 3
• Oral facial digital syndrome type 4 - See Orofaciodigital syndrome 4
• Oral facial digital syndrome type 5 - See Orofaciodigital syndrome 5
• Oral facial digital syndrome type 8 - See Orofaciodigital syndrome 8
• Oral facial digital syndrome type 9 - See Orofaciodigital syndrome 9
• Oral facial digital syndromes - See Orofaciodigital syndromes
• Oral facial dystonia - See Meige syndrome
• Oral gangrene - See Noma
• Oral leukoplakia
• Oral lichen planus - not a rare disease
• Oral lichenoid lesions - See Oral lichen planus - not a rare disease
• Oral pharyngeal disorders
• Oral squamous cell carcinoma
• Oral submucous fibrosis
• Oral-facial-digital syndrome - See Orofaciodigital syndromes
• Oral-facial-digital syndrome 1 - See Orofaciodigital syndrome 1
• Oral-facial-digital syndrome 10 - See Orofaciodigital syndrome 10
• Oral-facial-digital syndrome 12 - See Orofaciodigital syndrome 12
• Oral-facial-digital syndrome 13 - See Orofaciodigital syndrome 13
• Oral-facial-digital syndrome 5 - See Orofaciodigital syndrome 5
• Oral-facial-digital syndrome type 1 - See Orofaciodigital syndrome 1
• Oral-facial-digital syndrome type 11 - See Orofaciodigital syndrome 11
• Oral-facial-digital syndrome type 12 - See Orofaciodigital syndrome 12
• Oral-facial-digital syndrome type 13 - See Orofaciodigital syndrome 13
• Oral-facial-digital syndrome type 14 - See Orofaciodigital syndrome 14
• Oral-facial-digital syndrome type 2 - See Orofaciodigital syndrome 2
• Oral-facial-digital syndrome type 3 - See Orofaciodigital syndrome 3
• Oral-facial-digital syndrome type 4 - See Orofaciodigital syndrome 4
• Oral-facial-digital syndrome type 6 - See Orofaciodigital syndrome 6
• Oral-facial-digital syndrome type 8 - See Orofaciodigital syndrome 8
• Oral-facial-digital syndrome type 9 - See Orofaciodigital syndrome 9
• Oral-facial-digital syndrome with fibular aplasia - See Orofaciodigital syndrome 10
• Oral-facial-digital syndrome with hypoplastic epiglottis - See Orofaciodigital syndrome 8
• Oral-facial-digital syndrome with retinal abnormalities - See Orofaciodigital syndrome 9
• Oral-facial-digital syndrome with skeletal anomalies - See Orofaciodigital syndrome 11
• Oral-facial-digital syndrome XIII - See Orofaciodigital syndrome 13
• Oral-facial-digital syndromes - See Orofaciodigital syndromes
• Orbital cyst with cerebral and focal dermal malformations - See Oculocerebrocutaneous syndrome
• Orbital lymphangioma
• Orbital lymphoma
• Orbital melanoma
• Orbital varix
• Orbital venous varix - See Orbital varix
• ORC syndrome - See Oculorenocerebellar syndrome
• Orchidoblastoma - See Testicular yolk sac tumor
• Oregon type tyrosinemia - See Tyrosinemia type 2
• Organic acidemia
• Organic mood syndrome
• Organizing pneumonia - See Bronchiolitis obliterans organizing pneumonia
• Organoid nevus phakomatosis - See Linear nevus sebaceous syndrome
• Organoid nevus with sebaceous differentiation, a speckled-lentiginous nevus, and other associated anomalies - SeePhacomatosis pigmentokeratotica
• Ormond disease - See Retroperitoneal fibrosis
• Ormond's disease - See Retroperitoneal fibrosis
• Ornithine aminotransferase deficiency - See Gyrate atrophy of choroid and retina
• Ornithine carbamoyltransferase deficiency - See Ornithine transcarbamylase deficiency
• Ornithine ketoacid aminotransferase deficiency - See Gyrate atrophy of choroid and retina
• Ornithine transcarbamylase deficiency
• Ornithine translocase deficiency - See Ornithine translocase deficiency syndrome
• Ornithine translocase deficiency syndrome
• Ornithinemia
• Ornithosis - See Psittacosis
• Oroacral syndrome - See Oro-mandibular-limb hypogenesis syndrome
• Orocraniodigital syndrome - See Juberg-Hayward syndrome
• Orofacial cleft 11 - See Microphthalmia syndromic 6
• Oro-facial gangrene - See Noma
• Orofacial Granulomatosis
• Oro-facial noma - See Noma
• Orofaciodigital syndrome - See Orofaciodigital syndromes
• Orofaciodigital syndrome 1
• Orofaciodigital syndrome 10
• Orofaciodigital syndrome 11
• Orofaciodigital syndrome 12
• Orofaciodigital syndrome 13
• Orofaciodigital syndrome 14
• Orofaciodigital syndrome 2
• Orofaciodigital syndrome 3
• Orofaciodigital syndrome 4
• Orofaciodigital syndrome 5
• Orofaciodigital syndrome 6
• Orofaciodigital syndrome 8
• Orofaciodigital syndrome 9
• Orofaciodigital syndrome I - See Orofaciodigital syndrome 1
• Orofaciodigital syndrome II - See Orofaciodigital syndrome 2
• Orofaciodigital syndrome III - See Orofaciodigital syndrome 3
• Orofaciodigital syndrome IV - See Orofaciodigital syndrome 4
• Orofaciodigital syndrome IX - See Orofaciodigital syndrome 9
• Orofaciodigital syndrome type 12 - See Orofaciodigital syndrome 12
• Orofaciodigital syndrome type 13 - See Orofaciodigital syndrome 13
• Orofaciodigital syndrome type 14 - See Orofaciodigital syndrome 14
• Orofaciodigital syndrome type 6 - See Orofaciodigital syndrome 6
• Orofaciodigital syndrome type 8 - See Orofaciodigital syndrome 8
• Orofaciodigital syndrome type Figuera - See Orofaciodigital syndrome 10
• Orofaciodigital syndrome V - See Orofaciodigital syndrome 5
• Orofaciodigital syndrome VIII - See Orofaciodigital syndrome 8
• Orofaciodigital syndrome with fibular aplasia - See Orofaciodigital syndrome 10
• Orofaciodigital syndrome with retinal abnormalities - See Orofaciodigital syndrome 9
• Orofaciodigital syndrome with tibial dysplasia - See Orofaciodigital syndrome 4
• Orofaciodigital syndrome X - See Orofaciodigital syndrome 10
• Orofaciodigital syndrome XI - See Orofaciodigital syndrome 11
• Orofaciodigital syndrome XII - See Orofaciodigital syndrome 12
• Orofaciodigital syndrome XIII - See Orofaciodigital syndrome 13
• Orofaciodigital syndromes
• Oro-mandibular-limb hypogenesis syndrome
• Oropharyngeal cancer, adult
• Oropharyngeal cancer, childhood
• Oropharyngeal infection leading to secondary septic thrombophlebitis of the internal jugular vein - See Lemierre syndrome
• Orotate phosphoribosyltransferase and omp decarboxylase deficiency - See Orotic aciduria type 1
• Orotic aciduria II (formerly) - See Orotic aciduria type 1
• Orotic aciduria type 1
• Oroticaciduria 1 - See Orotic aciduria type 1
• Orotidylic pyrophosphorylase and orotidylic decarboxylase deficiency - See Orotic aciduria type 1
• Orstavik Lindemann Solberg syndrome - See Heart defect-tongue hamartoma-polysyndactyly syndrome
• Orthostatic hypotension (a symptom) - See Pure autonomic failure
• Orthostatic intolerance due to NET deficiency
• Orthostatic tremor, primary - See Primary orthostatic tremor
• ORW disease - See Hereditary hemorrhagic telangiectasia
• ORW2 - See Hereditary hemorrhagic telangiectasia type 2
• ORW3 - See Hereditary hemorrhagic telangiectasia type 3
• osASD - See Ostium secundum atrial septal defect
• OSCS - See Osteopathia striata cranial sclerosis
• Osebold-Remondini syndrome - See Brachydactyly type A6
• Oslam syndrome
• Osler Weber Rendu syndrome - See Hereditary hemorrhagic telangiectasia
• Osler Weber Rendu syndrome type 2 - See Hereditary hemorrhagic telangiectasia type 2
• Osler Weber Rendu syndrome type 3 - See Hereditary hemorrhagic telangiectasia type 3
• Osler-Rendu-Weber disease - See Hereditary hemorrhagic telangiectasia
• OSMED - See OSMED Syndrome
• OSMED Syndrome
• OSMF - See Oral submucous fibrosis
• Ossicular Malformations, familial
• Ossification of the posterior longitudinal ligament of the spine - not a rare disease
• Ossified ear cartilages with mental deficiency, muscle wasting, and bony changes - See Primrose syndrome
• Ossifying fibroma - See Osteofibrous dysplasia
• Osteitis deformans - See Paget disease of bone - not a rare disease
• Osteoarthropathy of fingers familial
• Osteoarthropathy, premature degenerative, of hip - See Beukes familial hip dysplasia
• Osteochondritis deformans - See Legg-Calve-Perthes disease
• Osteochondritis dissecans
• Osteochondritis dissecans, short stature, and early-onset osteoarthritis - See Familial osteochondritis dissecans
• Osteochondritis of tarsal/metatarsal bone - See Kohler disease
• Osteochondrodysplasia with rhizomelia, platyspondyly, callosal agenesis, thrombocytopenia, hydrocephalus, and hypertension - See Faye-Petersen-Ward-Carey syndrome
• Osteochondrodysplasias - See Skeletal dysplasias - not a rare disease
• Osteochondroma
• Osteochondromuscular dystrophy - See Schwartz Jampel syndrome
• Osteochondrosis
• Osteochondrosis deformans tibiae - See Blount disease
• Osteochondrosis deformans tibiae, familial infantile type - See Blount disease
• Osteochondrosis of the metatarsal head, usually the second - See Freiberg's disease
• Osteochondrosis of the tarsal bone - See Kohler disease
• Osteoclastoma - See Giant cell tumor of bone
• Osteocraniosplenic syndrome - See Gracile bone dysplasia
• Osteocraniostenosis - See Gracile bone dysplasia
• Osteodysgenesis, multisynostotic with fractures - See Antley Bixler syndrome
• Osteodysplasia familial Anderson type
• Osteodysplastic primordial dwarfism type 2 - See Microcephalic osteodysplastic primordial dwarfism type 2
• Osteodysplastic primordial dwarfism type I - See Microcephalic osteodysplastic primordial dwarfism type 1
• Osteodysplasty of Melnick and Needles - See Melnick-Needles syndrome
• Osteodysplasty precocious of Danks Mayne and Kozlowski
• Osteofibrous dysplasia
• Osteogenesis imperfecta
• Osteogenesis imperfecta congenita - See Osteogenesis imperfecta type II
• Osteogenesis imperfecta congenita perinatal lethal form - See Osteogenesis imperfecta type II
• Osteogenesis imperfecta Levin type
• Osteogenesis imperfecta ocular form - See Osteoporosis-pseudoglioma syndrome
• Osteogenesis imperfecta retinopathy seizures intellectual deficit - See Al Gazali Sabrinathan Nair syndrome
• Osteogenesis imperfecta sillence type II/III without abnormality of type I collagen - See Osteogenesis imperfecta type IX
• Osteogenesis imperfecta tarda - See Osteogenesis imperfecta type I
• Osteogenesis imperfecta type - See Osteogenesis imperfecta type VI
• Osteogenesis imperfecta type 10 - See Osteogenesis imperfecta
• Osteogenesis imperfecta type 11 - See Osteogenesis imperfecta
• Osteogenesis imperfecta type 2 - See Osteogenesis imperfecta type II
• Osteogenesis imperfecta type 8 - See Osteogenesis imperfecta type VIII
• Osteogenesis imperfecta type 9 - See Osteogenesis imperfecta type IX
• Osteogenesis imperfecta type I
• Osteogenesis imperfecta type II
• Osteogenesis imperfecta type III
• Osteogenesis imperfecta type IV
• Osteogenesis imperfecta type IX
• Osteogenesis imperfecta type V
• Osteogenesis imperfecta type VI
• Osteogenesis imperfecta type VII
• Osteogenesis imperfecta type VIII
• Osteogenesis imperfecta type X - See Osteogenesis imperfecta
• Osteogenesis imperfecta type XI - See Osteogenesis imperfecta
• Osteogenesis imperfecta with blue sclerae - See Osteogenesis imperfecta type I
• Osteogenesis imperfecta with congenital joint contractures - See Bruck syndrome 1
• Osteogenesis imperfecta with normal sclerae - See Osteogenesis imperfecta type IV
• Osteogenesis imperfecta with unusual skeletal lesions - See Osteogenesis imperfecta Levin type
• Osteogenesis imperfecta, progressively deforming with normal sclerae - See Osteogenesis imperfecta type III
• Osteogenic sarcoma - See Osteosarcoma
• Osteoglophonic dwarfism - See Osteoglophonic dysplasia
• Osteoglophonic dysplasia
• Osteolysis massive - See Gorham's disease
• Osteolysis syndrome recessive
• Osteolysis, distal, with short stature, mental retardation, and characteristic facial appearance - See Osteolysis syndrome recessive
• Osteolysis, familial expansile - See Polyostotic osteolytic dysplasia, hereditary expansile
• Osteomalacia
• Osteomesopyknosis
• Osteomyelitis
• Osteo-Onychodysplasia - See Nail-patella syndrome
• Osteopathia condensans disseminata - See Osteopoikilosis
• Osteopathia condensans disseminata - See Buschke Ollendorff syndrome
• Osteopathia striata - cranial sclerosis - See Osteopathia striata cranial sclerosis
• Osteopathia striata associated with familial dermopathy and white forelock - See Osteopathia striata with pigmentary dermopathy including white forelock
• Osteopathia striata cranial sclerosis
• Osteopathia striata with pigmentary dermopathy including white forelock
• Osteopathia striata-cranial sclerosis syndrome - See Osteopathia striata cranial sclerosis
• Osteopenia and sparse hair
• Osteopenia mental retardation sparse hair - See Osteopenia and sparse hair
• Osteopetroses - See Osteopetrosis
• Osteopetrosis
• Osteopetrosis and infantile neuroaxonal dystrophy
• Osteopetrosis and related disorders - See Osteopetrosis
• Osteopetrosis autosomal dominant type 1
• Osteopetrosis autosomal dominant type 2
• Osteopetrosis autosomal recessive 1
• Osteopetrosis autosomal recessive 2
• Osteopetrosis autosomal recessive 3
• Osteopetrosis autosomal recessive 4
• Osteopetrosis autosomal recessive 5
• Osteopetrosis autosomal recessive 6
• Osteopetrosis autosomal recessive 7
• Osteopetrosis autosomal recessive intermediate form - See Osteopetrosis autosomal recessive 6
• Osteopetrosis infantile malignant 1 - See Osteopetrosis autosomal recessive 1
• Osteopetrosis infantile malignant 2 - See Osteopetrosis autosomal recessive 4
• Osteopetrosis infantile malignant 3 - See Osteopetrosis autosomal recessive 5
• Osteopetrosis osteoclast-poor - See Osteopetrosis autosomal recessive 2
• Osteopetrosis osteoclast-poor with hypogammaglobulinemia - See Osteopetrosis autosomal recessive 7
• Osteopetrosis with renal tubular acidosis - See Osteopetrosis autosomal recessive 3
• Osteopoikilosis
• Osteopoikilosis and dacryocystitis
• Osteopoikilosis-short stature-intellectual disability syndrome - See 12q14 microdeletion syndrome
• Osteoporosis oculocutaneous hypopigmentation syndrome
• Osteoporosis pseudoglioma syndrome - See Osteoporosis-pseudoglioma syndrome
• Osteoporosis, juvenile - See Juvenile osteoporosis
• Osteoporosis-pseudoglioma syndrome
• Osteopsathyrosis - See Osteogenesis imperfecta
• Osteosarcoma
• Osteosarcoma, limb anomalies (clinodactyly, absence of digital ray in foot, bilateral radioulnar synostosis) and macrocytosis without anemia - See Oslam syndrome
• Osteosarcoma, limb anomalies, and erythroid macrocytosis with megaloblastic marrow - See Oslam syndrome
• Osteosclerosis fragilis - See Osteopetrosis
• Osteosclerosis of the skull and enlarged mandible - See Van Buchem disease type 2
• Osteosclerosis with ichthyosis and POF - See Osteosclerosis with ichthyosis and premature ovarian failure
• Osteosclerosis with ichthyosis and premature ovarian failure
• Osteosclerosis, autosomal dominant - See Worth type autosomal dominant osteosclerosis
• Osteosclerosis, autosomal dominant, Worth type - See Worth type autosomal dominant osteosclerosis
• Ostertag type amyloidosis - See Amyloidosis familial visceral
• Ostium primum ASD - See Atrial septal defect ostium primum
• Ostium secundum ASD - See Ostium secundum atrial septal defect
• Ostium secundum atrial septal defect
• Ostravik-Lindemann-Solberg syndrome - See Heart defect-tongue hamartoma-polysyndactyly syndrome
• OT - See Primary orthostatic tremor
• OTC deficiency - See Ornithine transcarbamylase deficiency
• OTCD - See Ornithine transcarbamylase deficiency
• Otodental dysplasia
• Otofaciocervical syndrome
• Otoonychoperoneal syndrome
• Oto-onycho-peroneal syndrome - See Otoonychoperoneal syndrome
• Oto-Palatal-digital syndrome
• Otopalatodigital syndrome type 1 - See Oto-palato-digital syndrome type 1
• Oto-palato-digital syndrome type 1
• Otopalatodigital syndrome type 2 - See Oto-palato-digital syndrome type 2
• Oto-palato-digital syndrome type 2
• Otosclerosis, familial
• Otospondylomegaepiphyseal dysplasia - See OSMED Syndrome
• Oto-Spondylo-Mega-Epiphyseal Dysplasia - See OSMED Syndrome
• Otto syndrome - See Arthrogryposis multiplex congenita
• Otulipenia
• OTX2-related eye disorders - See Microphthalmia syndromic 5
• Oudtshoorn skin - See Keratolytic winter erythema
• Ouvrier Billson syndrome
• Ovarian Brenner tumor - See Brenner tumor of ovary
• Ovarian cancer
• Ovarian cancer, epithelial - See Ovarian epithelial cancer
• Ovarian carcinoma - See Ovarian cancer
• Ovarian carcinoma, childhood - See Childhood ovarian cancer
• Ovarian carcinosarcoma
• Ovarian dysgenesis with sensorineural deafness - See Perrault syndrome
• Ovarian epithelial cancer
• Ovarian epithelial carcinoma - See Ovarian epithelial cancer
• Ovarian germ cell tumor
• Ovarian gynandroblastoma - See Gynandroblastoma
• Ovarian insufficiency due to FSH resistance
• Ovarian insufficiency, familial
• Ovarian low malignant potential tumor
• Ovarian malignant mixed epithelial mesenchymal tumor - See Ovarian carcinosarcoma
• Ovarian malignant mixed Müllerian tumor - See Ovarian carcinosarcoma
• Ovarian remnant syndrome
• Ovarian sex cord tumor with annular tubules
• Ovarian sex cord-stromal tumor - See Ovarian sex cord tumor with annular tubules
• Ovarian small cell carcinoma
• Overgrowth - craniosynostosis - arthrogryposis - See Richieri-Costa Guion-Almeida Cohen syndrome
• Overgrowth syndrome with accelerated skeletal maturation, unusual facies, and camptodactyly - See Weaver syndrome
• Overhydrated hereditary stomatocytosis
• Overlap connective tissue disease - See MASS phenotype
• Ovoid neutrophil nuclei, developmental delay, epilepsy and skeletal abnormalities - See Pelger-Huet anomaly
• Ovoid pupils - See Egg shaped pupils
• Oxalosis 1 - See Primary hyperoxaluria type 1
• Oxalosis 2 - See Primary hyperoxaluria type 2
• Oxoglutaricaciduria - See Alpha-ketoglutarate dehydrogenase deficiency
• Oxoprolinase deficiency - See Glutathione synthetase deficiency
• Oxoprolinuria due to 5-oxoprolinase deficiency - See 5-oxoprolinase deficiency