U.S. flag

An official website of the United States government

Format

Send to:

Choose Destination

Pontocerebellar hypoplasia, type 1F(PCH1F)

MedGen UID:
1785905
Concept ID:
C5543331
Disease or Syndrome
Synonyms: PCH1F; PONTOCEREBELLAR HYPOPLASIA, TYPE 1F
 
Gene (location): EXOSC1 (10q24.1)
 
Monarch Initiative: MONDO:0030261
OMIM®: 619304

Definition

Pontocerebellar hypoplasia type 1F (PCH1F) is an autosomal recessive neurologic disorder characterized by hypotonia, global developmental delay, poor overall growth, and dysmorphic facial features. Brain imaging shows pontocerebellar hypoplasia, thin corpus callosum, cerebral atrophy, and delayed myelination (summary by Somashekar et al., 2021). For a phenotypic description and a discussion of genetic heterogeneity of PCH, see PCH1A (607596). [from OMIM]

Clinical features

From HPO
Growth delay
MedGen UID:
99124
Concept ID:
C0456070
Pathologic Function
A deficiency or slowing down of growth pre- and postnatally.
Cerebral atrophy
MedGen UID:
116012
Concept ID:
C0235946
Disease or Syndrome
Atrophy (wasting, decrease in size of cells or tissue) affecting the cerebrum.
Cerebellar hypoplasia
MedGen UID:
120578
Concept ID:
C0266470
Congenital Abnormality
Cerebellar hypoplasia is a descriptive term implying a cerebellum with a reduced volume, but a normal shape and is stable over time.
Hypoplasia of the corpus callosum
MedGen UID:
138005
Concept ID:
C0344482
Congenital Abnormality
Underdevelopment of the corpus callosum.
Global developmental delay
MedGen UID:
107838
Concept ID:
C0557874
Finding
A delay in the achievement of motor or mental milestones in the domains of development of a child, including motor skills, speech and language, cognitive skills, and social and emotional skills. This term should only be used to describe children younger than five years of age.
Hyporeflexia
MedGen UID:
195967
Concept ID:
C0700078
Finding
Reduction of neurologic reflexes such as the knee-jerk reaction.
Hypoplasia of the pons
MedGen UID:
341246
Concept ID:
C1848529
Finding
Underdevelopment of the pons.
Delayed CNS myelination
MedGen UID:
867393
Concept ID:
C4021758
Anatomical Abnormality
Delayed myelination in the central nervous system.
Hypotonia
MedGen UID:
10133
Concept ID:
C0026827
Finding
Hypotonia is an abnormally low muscle tone (the amount of tension or resistance to movement in a muscle). Even when relaxed, muscles have a continuous and passive partial contraction which provides some resistance to passive stretching. Hypotonia thus manifests as diminished resistance to passive stretching. Hypotonia is not the same as muscle weakness, although the two conditions can co-exist.
Retrognathia
MedGen UID:
19766
Concept ID:
C0035353
Congenital Abnormality
An abnormality in which the mandible is mislocalised posteriorly.
Microcephaly
MedGen UID:
1644158
Concept ID:
C4551563
Finding
Head circumference below 2 standard deviations below the mean for age and gender.
High forehead
MedGen UID:
65991
Concept ID:
C0239676
Finding
An abnormally increased height of the forehead.
Telecanthus
MedGen UID:
140836
Concept ID:
C0423113
Finding
Distance between the inner canthi more than two standard deviations above the mean (objective); or, apparently increased distance between the inner canthi.
Smooth philtrum
MedGen UID:
222980
Concept ID:
C1142533
Finding
Flat skin surface, with no ridge formation in the central region of the upper lip between the nasal base and upper vermilion border.
Depressed nasal bridge
MedGen UID:
373112
Concept ID:
C1836542
Finding
Posterior positioning of the nasal root in relation to the overall facial profile for age.
Thick vermilion border
MedGen UID:
332232
Concept ID:
C1836543
Finding
Increased width of the skin of vermilion border region of upper lip.
Anteverted nares
MedGen UID:
326648
Concept ID:
C1840077
Finding
Anteriorly-facing nostrils viewed with the head in the Frankfurt horizontal and the eyes of the observer level with the eyes of the subject. This gives the appearance of an upturned nose (upturned nasal tip).
Long philtrum
MedGen UID:
351278
Concept ID:
C1865014
Finding
Distance between nasal base and midline upper lip vermilion border more than 2 SD above the mean. Alternatively, an apparently increased distance between nasal base and midline upper lip vermilion border.
Strabismus
MedGen UID:
21337
Concept ID:
C0038379
Disease or Syndrome
A misalignment of the eyes so that the visual axes deviate from bifoveal fixation. The classification of strabismus may be based on a number of features including the relative position of the eyes, whether the deviation is latent or manifest, intermittent or constant, concomitant or otherwise and according to the age of onset and the relevance of any associated refractive error.
Blue sclerae
MedGen UID:
154236
Concept ID:
C0542514
Finding
An abnormal bluish coloration of the sclera.

Supplemental Content