We reported a PRRT2 heterozygous mutation (c.604-607delTCAC, p.S202Hfs*25) in a 3-generation Chinese family with infantile convulsion and choreoathetosis and paroxysmal kinesigenic dyskinesia.
This study analysed PRRT2 gene mutations in 51 families with paroxysmal kinesigenic dyskinesia or infantile convulsions and choreoathetosis by direct sequencing.
PRRT2 is the gene recently associated with paroxysmal kinesigenic dyskinesia (PKD), benign familial infantile epilepsy, and choreoathetosis infantile convulsions.
PKD is characterized by recurrent uni- or bilateral choreoathetosis and usually represents an autosomal dominant inherited disorder caused by PRRT2 gene mutations.
Benign familial infantile epilepsy (41.7%; n = 602), paroxysmal kinesigenic dyskinesia (38.7%; n = 560) and infantile convulsions and choreoathetosis (14.3%; n = 206) constitute the vast majority of PRRT2-associated diseases, leaving 76 patients (5.3%) with a different primary diagnosis.
Mutations in PRRT2 have been described in paroxysmal kinesigenic dyskinesia (PKD) and infantile convulsions with choreoathetosis (PKD with infantile seizures), and recently also in some families with benign familial infantile seizures (BFIS) alone.
PRRT2 mutations have recently been shown to cause various childhood-onset episodic syndromes including paroxysmal kinesigenic dyskinesia, infantile convulsions with choreoathetosis syndrome, and benign familial infantile epilepsy.
Up to 25-30% of HPRT deficient patients, indicated as neurological variants or HPRT-related hyperuricemia with neurological dysfunction (HRND), may develop neurological manifestation, from mild to severe; the most serious ones manifesting in the devastating Lesch-Nyhan syndrome, characterized by choreoathetosis or self-mutilation.
We conclude that deletions at 14q13.3 adjacent to but not involving NKX2-1 can cause choreoathetosis, congenital hypothyroidism, and neonatal respiratory distress syndrome.
Loss-of-function mutations in a human AMPA receptor-associated protein, ferric chelate reductase 1-like (FRRS1L), are associated with a devastating neurological condition incorporating choreoathetosis, cognitive deficits and epileptic encephalopathies.
The complete deficiency of HPRT is diagnostic of Lesch-Nyhan syndrome manifested by choreoathetosis, spasticity, mental retardation, and self-injurious behavior.
We describe a neurological disorder with epilepsy and prominent choreoathetosis caused by biallelic pathogenic variants in FRRS1L, which encodes an AMPA receptor outer-core protein.
We excluded linkage to 11 regions containing genes associated with chorea and myokymia: 1) the Huntington disease gene on chromosome 4p; 2) the paroxysmal dystonic choreoathetosis gene at 2q34; 3) the dentatorubral-pallidoluysian atrophy gene at 12p13; 4) the choreoathetosis/spasticity disease locus on 1p that lies in a region containing a cluster of potassium (K+) channel genes; 5) the episodic ataxia type 1 (EA1) locus on 12p that contains the KCNA1 gene and two other voltage-gated K+ channel genes, KCNA5 and KCNA6; 6) the chorea-acanthocytosis locus on 9q21; 7) the Huntington-like syndrome on 20p; 8) the paroxysmal kinesigenic dyskinesia locus on 16p11.2-q11.2; 9) the benign hereditary chorea locus on 14q; 10) the SCA type 5 locus on chromosome 11; and 11) the chromosome 19 region that contains several ion channels and the CACNA1A gene, a brain-specific P/Q-type calcium channel gene associated with ataxia and hemiplegic migraine.
Ataxia with oculomotor apraxia (ataxia-telangiectasia-like syndrome [AOA]; MIM 208920) is an autosomal recessive disorder characterized by ataxia, oculomotor apraxia, and choreoathetosis.