Ataxia, and Atrial septal defect

Autism, the prototypic pervasive developmental disorder (PDD), is usually apparent by 3 years of age. It is characterized by a triad of limited or absent verbal communication, a lack of reciprocal social interaction or responsiveness, and restricted, stereotypical, and ritualized patterns of interests and behavior (Bailey et al., 1996; Risch et al., 1999). 'Autism spectrum disorder,' sometimes referred to as ASD, is a broader phenotype encompassing the less severe disorders Asperger syndrome (see ASPG1; {608638}) and pervasive developmental disorder, not otherwise specified (PDD-NOS). 'Broad autism phenotype' includes individuals with some symptoms of autism, but who do not meet the full criteria for autism or other disorders. Mental retardation coexists in approximately two-thirds of individuals with ASD, except for Asperger syndrome, in which mental retardation is conspicuously absent (Jones et al., 2008). Genetic studies in autism often include family members with these less stringent diagnoses (Schellenberg et al., 2006).Levy et al. (2009) provided a general review of autism and autism spectrum disorder, including epidemiology, characteristics of the disorder, diagnosis, neurobiologic hypotheses for the etiology, genetics, and treatment options.

AUTISM, SUSCEPTIBILITY TO, X-LINKED 4; AUTSX4 Is also known as chromosome xp22 deletion syndrome

• Intellectual disability
• Seizures
• Global developmental delay
• Generalized hypotonia
• Ataxia

SOURCES: OMIM MENDELIAN

Brain-lung-thyroid syndrome is a rare disorder characterized by congenital hypothyroidism (CH), infant respiratory distress syndrome (IRDS) and benign hereditary chorea (BHC; see these terms).

BRAIN-LUNG-THYROID SYNDROME Is also known as choreoathetosis-hypothyroidism-neonatal respiratory distress syndrome|brain-lung-thyroid syndrome

• Global developmental delay
• Generalized hypotonia
• Ataxia
• Muscular hypotonia
• Motor delay

SOURCES: OMIM MESH ORPHANET MENDELIAN

Combined oxidative phosphorylation deficiency type 3 is an extremely rare clinically heterogenous disorder described in about 5 patients to date. Clinical signs included hypotonia, lactic acidosis, and hepatic insufficiency, with progressive encephalomyopathy or hypertrophic cardiomyopathy.

FATAL MITOCHONDRIAL DISEASE DUE TO COMBINED OXIDATIVE PHOSPHORYLATION DEFECT TYPE 3 Is also known as fatal mitochondrial disease due to coxpd3|encephalomyopathy, respiratory failure, and lactic acidosis|concentric cardiomyopathy, hypotonia, and lactic acidosis

• Seizures
• Global developmental delay
• Generalized hypotonia
• Ataxia
• Growth delay

SOURCES: OMIM MESH ORPHANET MENDELIAN

L-2-hydroxyglutaric aciduria is a primarily neurological form of 2-hydroxyglutaric aciduria (see this term) characterized by psychomotor retardation, cerebellar ataxia and variable macrocephaly or epilepsy.

L-2-HYDROXYGLUTARIC ACIDURIA Is also known as l-2-hga|l-2-hydroxyglutaric acidemia

• Intellectual disability
• Seizures
• Global developmental delay
• Hearing impairment
• Ataxia

SOURCES: OMIM ORPHANET MENDELIAN

Macrocephaly-intellectual disability-left ventricular non compaction syndrome is a rare, genetic, syndromic intellectual disability characterized by motor and cognitive developmental delay with language impairment, macrocephaly, hypotonia, dysmorphic facial features (including long face, slanting palpebral fissures and prominent, flattened nose) and left ventricular noncompaction cardiomyopathy. Patients also present skeletal abnormalities (e.g. scoliosis, finger clinodactyly, pes planus), slender build and shy behavior. Strabismus and various neurological signs (including ataxia, tremor and hyperreflexia) may be associated, as well as epilepsy, autism and MRI findings showing a small cerebellum and abnormalities of the corpus callosum. A phenotypic variant with no cardiac involvement has been reported.

MACROCEPHALY-INTELLECTUAL DISABILITY-LEFT VENTRICULAR NON COMPACTION SYNDROME Is also known as mrxsml|mental retardation, x-linked, syndromic, mircsof-langouet type

• Intellectual disability
• Seizures
• Global developmental delay
• Generalized hypotonia
• Scoliosis

SOURCES: OMIM ORPHANET MENDELIAN

Thiamine-responsive megaloblastic anemia (TRMA) is characterized by a triad of megaloblastic anemia, non-type I diabetes mellitus, and sensorineural deafness.

THIAMINE-RESPONSIVE MEGALOBLASTIC ANEMIA SYNDROME Is also known as thmd1|trma|thiamine-responsive megaloblastic anemia with diabetes mellitus and sensorineural deafness|rogers syndrome|thiamine-responsive myelodysplasia|thiamine metabolism dysfunction syndrome 1 (megaloblastic anemia, diabetes mellitus, and deafness type

• Seizures
• Global developmental delay
• Short stature
• Hearing impairment
• Microcephaly

SOURCES: MESH ORPHANET OMIM MENDELIAN

Joubert syndrome is a genetically heterogeneous autosomal recessive disorder characterized by a specific hindbrain malformation, which is referred to as the 'molar tooth sign' (MTS) on brain MRI, hypotonia, developmental delay, oculomotor apraxia, and breathing abnormalities. The complex brainstem malformation consists of cerebellar vermian hypoplasia/aplasia, thickened and reoriented superior cerebellar peduncles, and an abnormally large interpeduncular fossa, giving the appearance of a molar tooth on transaxial slices (Maria et al., 1997). Additional features sometimes associated with Joubert syndrome include retinal anomalies, polydactyly, hepatic fibrosis, and renal disease. These related disorders are often referred to as 'cerebellooculorenal syndromes' (CORSs) (Chance et al., 1999; Satran et al., 1999).

JOUBERT SYNDROME 2; JBTS2 Is also known as cors2|cerebellooculorenal syndrome 2

• Intellectual disability
• Global developmental delay
• Generalized hypotonia
• Ataxia
• Hypertelorism

SOURCES: MESH OMIM MENDELIAN

Chédiak-Higashi syndrome (CHS) is a rare severe genetic disorder generally characterized by partial oculocutaneous albinism (OCA, see this term), severe immunodeficiency, mild bleeding, neurological dysfunction and lymphoproliferative disorder. A classic, early-onset form and an attenuated, later-onset form (Atypical CHS; see this term) have been described.

CHÉDIAK-HIGASHI SYNDROME Is also known as chÉdiak-higashi-steinbrink syndrome|chÉdiak-higashi disease

• Intellectual disability
• Seizures
• Global developmental delay
• Generalized hypotonia
• Ataxia

SOURCES: OMIM ORPHANET MESH MENDELIAN

Miller-Dieker Syndrome (MDS) is a contiguous gene deletion syndrome of chromosome 17p13.3, characterised by classical lissencephaly (lissencephaly type 1) and distinct facial features. Additional congenital malformations can be part of the condition.

MILLER-DIEKER SYNDROME Is also known as monosomy 17p13.3|lissencephaly due to 17p13.3 deletion|mds|telomeric deletion 17p

• Intellectual disability
• Seizures
• Microcephaly
• Ataxia
• Growth delay

SOURCES: ORPHANET OMIM MENDELIAN