Polymicrogyria due to TUBB2B mutation

General Information (adopted from Orphanet):

Synonyms, Signs: PMGYSA
Number of Symptoms 22
OrphanetNr: 300573
OMIM Id: 610031
ICD-10: Q04.3
UMLs:
MeSH:
MedDRA:
Snomed:

Prevalence, inheritance and age of onset:

Prevalence: No data available.
Inheritance: Autosomal dominant
[Orphanet]
Age of onset: Neonatal
Infancy
[Orphanet]

Disease classification (adopted from Orphanet):

Parent Diseases: Bilateral frontal polymicrogyria
 -Rare developmental defect during embryogenesis
 -Rare genetic disease
 -Rare neurologic disease

Symptom Information: Sort by abundance 

1
 (HPO:0000252) Microcephaly 832 / 7739
2
 (HPO:0002307) Drooling 43 / 7739
3
 (HPO:0001491) Congenital fibrosis of extraocular muscles 9 / 7739
4
 (HPO:0007941) Limited extraocular movements 7 / 7739
5
 (HPO:0001328) Specific learning disability 114 / 7739
6
 (HPO:0001263) Global developmental delay 853 / 7739
7
 (HPO:0001250) Seizures 1245 / 7739
8
 (HPO:0001249) Intellectual disability 1089 / 7739
9
 (HPO:0001270) Motor delay 322 / 7739
10
 (OMIM) Oromotor dyspraxia 2 / 7739
11
 (OMIM) Contralateral hemiparesis, congenital 2 / 7739
12
 (OMIM) Malformations of cortical development, variable 2 / 7739
13
 (HPO:0001302) Pachygyria 60 / 7739
14
 (OMIM) Neuronal migration defect 4 / 7739
15
 (OMIM) Frontotemporoparietal cortical dysplasia 2 / 7739
16
 (OMIM) Brainstem abnormalities 3 / 7739
17
 (HPO:0002079) Hypoplasia of the corpus callosum 161 / 7739
18
 (HPO:0001274) Agenesis of corpus callosum 142 / 7739
19
 (OMIM) Irregular folding of the cortex 2 / 7739
20
 (HPO:0001321) Cerebellar hypoplasia 114 / 7739
21
 (OMIM) Polymicrogyria, asymmetric or symmetric 2 / 7739
22
 (OMIM) Contralateral hemianopsia (1 family) 2 / 7739

Associated genes:

ClinVar (via SNiPA)

Gene symbol Variation Clinical significance Reference

Additional Information:

Description: (OMIM) Polymicrogyria is a malformation of cortical development characterized by an excessive number of small gyri with abnormal lamination (Chang et al., 2006).

See 606854 for a description of hereditary bilateral frontoparietal polymicrogyria (BFPP).
Clinical Description OMIM Caraballo et al. (2000) reported a mother and son with unilateral right focal polymicrogyria. Both had cognitive impairment (IQ of 85 and 80, respectively) and congenital contralateral hemiparesis. The son also had focal seizures. Brain imaging of both ...
Molecular genetics OMIM In 4 unrelated patients and a fetus with asymmetric polymicrogyria, Jaglin et al. (2009) identified 5 different heterozygous mutations in the TUBB2B gene (see, e.g., 612850.0001-612850.0003). In vitro studies of some of the mutant proteins showed impaired formation ...