Multiple congenital anomalies-hypotonia-seizures syndrome type 2

General Information (adopted from Orphanet):

Synonyms, Signs: MCAHS2
MCAHS type 2
Number of Symptoms 64
OrphanetNr: 300496
OMIM Id: 300868
ICD-10: Q87.8
UMLs:
MeSH:
MedDRA:
Snomed:

Prevalence, inheritance and age of onset:

Prevalence: No data available.
Inheritance: X-linked recessive
[Orphanet]
Age of onset: Neonatal
Infancy
[Orphanet]

Disease classification (adopted from Orphanet):

Parent Diseases: Congenital disorder of glycosylation with developmental anomaly
 -Rare developmental defect during embryogenesis
 -Rare genetic disease
Congenital disorder of glycosylation with epilepsy as a major feature
 -Rare genetic disease
 -Rare neurologic disease
Disorder of glycosphingolipid and glycosylphosphatidylinositol anchor glycosylation
 -Rare genetic disease
Genetic multiple congenital anomalies/dysmorphic syndrome
 -Rare genetic disease
Multiple congenital anomalies/dysmorphic syndrome-intellectual deficit
 -Rare developmental defect during embryogenesis
 -Rare genetic disease

Symptom Information: Sort by abundance 

1
 (HPO:0000076) Vesicoureteral reflux rare [HPO:skoehler] 94 / 7739
2
 (HPO:0000081) Duplicated collecting system rare [HPO:skoehler] 16 / 7739
3
 (HPO:0002714) Downturned corners of mouth 98 / 7739
4
 (HPO:0000256) Macrocephaly 298 / 7739
5
 (HPO:0000160) Narrow mouth 188 / 7739
6
 (HPO:0000212) Gingival overgrowth 43 / 7739
7
 (HPO:0000687) Widely spaced teeth 40 / 7739
8
 (HPO:0000260) Wide anterior fontanel 55 / 7739
9
 (HPO:0000463) Anteverted nares 305 / 7739
10
 (HPO:0000347) Micrognathia 426 / 7739
11
 (HPO:0005484) Postnatal microcephaly 32 / 7739
12
 (HPO:0000207) Triangular mouth 8 / 7739
13
 (HPO:0000218) High palate 356 / 7739
14
 (HPO:0000270) Delayed cranial suture closure 33 / 7739
15
 (HPO:0001476) Delayed closure of the anterior fontanelle 23 / 7739
16
 (HPO:0000691) Microdontia 104 / 7739
17
 (HPO:0000582) Upslanted palpebral fissure 185 / 7739
18
 (HPO:0005280) Depressed nasal bridge 381 / 7739
19
 (HPO:0000269) Prominent occiput 43 / 7739
20
 (HPO:0000239) Large fontanelles 135 / 7739
21
 (HPO:0000470) Short neck 345 / 7739
22
 (HPO:0000272) Malar flattening 277 / 7739
23
 (HPO:0000280) Coarse facial features 189 / 7739
24
 (HPO:0100704) Cortical visual impairment 28 / 7739
25
 (HPO:0000365) Hearing impairment 539 / 7739
26
 (HPO:0000396) Overfolded helix 21 / 7739
27
 (HPO:0200134) Epileptic encephalopathy 42 / 7739
28
 (HPO:0011398) Central hypotonia 12 / 7739
29
 (HPO:0002521) Hypsarrhythmia 43 / 7739
30
 (HPO:0001344) Absent speech 57 / 7739
31
 (HPO:0001347) Hyperreflexia 363 / 7739
32
 (HPO:0002123) Generalized myoclonic seizures 62 / 7739
33
 (HPO:0001371) Flexion contracture 220 / 7739
34
 (HPO:0002240) Hepatomegaly rare [HPO:skoehler] 467 / 7739
35
 (HPO:0001394) Cirrhosis rare [HPO:skoehler] 102 / 7739
36
 (HPO:0001520) Large for gestational age 34 / 7739
37
 (HPO:0003517) Birth length greater than 97th percentile 4 / 7739
38
 (HPO:0001792) Small nail 55 / 7739
39
 (HPO:0001051) Seborrheic dermatitis rare [HPO:skoehler] 25 / 7739
40
 (HPO:0008064) Ichthyosis rare [HPO:skoehler] 108 / 7739
41
 (HPO:0001631) Atria septal defect 274 / 7739
42
 (HPO:0003155) Elevated alkaline phosphatase rare [HPO:skoehler] 52 / 7739
43
 (HPO:0001324) Muscle weakness 859 / 7739
44
 (HPO:0010547) Muscle flaccidity 466 / 7739
45
 (HPO:0001252) Muscular hypotonia 990 / 7739
46
 (HPO:0008947) Infantile muscular hypotonia 482 / 7739
47
 (HPO:0008936) Muscular hypotonia of the trunk 77 / 7739
48
 (OMIM) High birth weight 2 / 7739
49
 (HPO:0012448) Delayed myelination 51 / 7739
50
 (HPO:0001419) X-linked recessive inheritance 189 / 7739
51
 (OMIM) White matter immaturity 1 / 7739
52
 (HPO:0007361) Abnormality of the pons 1 / 7739
53
 (HPO:0002529) Neuronal loss in central nervous system 37 / 7739
54
 (OMIM) Dysplastic pons 1 / 7739
55
 (HPO:0001522) Death in infancy 275 / 7739
56
 (HPO:0001321) Cerebellar hypoplasia 114 / 7739
57
 (HPO:0001341) Olfactory lobe agenesis 5 / 7739
58
 (OMIM) Absence of the olfactory bulbs and tracts 1 / 7739
59
 (HPO:0001331) Absent septum pellucidum 16 / 7739
60
 (OMIM) Long birth length 1 / 7739
61
 (OMIM) Abnormal cortical lamination 1 / 7739
62
 (HPO:0002120) Cerebral cortical atrophy 187 / 7739
63
 (OMIM) Short, anteverted nose 1 / 7739
64
 (HPO:0002079) Hypoplasia of the corpus callosum 161 / 7739

Associated genes:

ClinVar (via SNiPA)

Gene symbol Variation Clinical significance Reference

Additional Information:

Description: (OMIM) Multiple congenital anomalies-hypotonia-seizures syndrome-2 is an X-linked recessive developmental disorder characterized by dysmorphic features, neonatal hypotonia, myoclonic seizures, and variable congenital anomalies involving the central nervous, cardiac, and urinary systems. Most affected individuals die in infancy (summary by ...
Clinical Description OMIM Johnston et al. (2012) reported a family in which 2 brothers had a lethal multiple congenital anomaly disorder. Both infants were born by Cesarean section due to breech presentation and were noted to have large size at birth. ...
Molecular genetics OMIM By exome sequencing of the X chromosome in a family with multiple congenital anomalies-hypotonia-seizures syndrome-2, Johnston et al. (2012) identified a germline mutation in the PIGA gene (R412X; 311770.0011). Two affected boys carried the mutation, and 2 obligate ...