Spectrum of pontocerebellar hypoplasia in 13 girls and boys with CASK mutations: confirmation of a recognizable phenotype and first description of a male mosaic patient

Table 1 Classification of PCH

PCH	Type 1	Type 2	Type 3	Type 4	Type 5	Type 6	Type 7
Distinctive features	Anterior horn cell degeneration	Dyskinetic movements Seizures (frequent)	Seizures Short stature Optic atrophy	Severe prenatal form of PCH2 with: Polyhydramnios Contractures Myoclonus Apneic episodes Early postnatal death	Severe prenatal form of type 2 with: Fetal onset of seizure-like activity Early postnatal death	Severe neonatal encephalopathy with: Hypotonia, and inconstantly Intractable seizures Edema Increased lactate Mitochondrial respiratory chain defects	Hypotonia Apneic episodes Seizures Vanishing testis
Inheritance	AR	AR	AR	AR	AR	AR	Unknown
Genes or loci	VRK1	TSEN54	7q11-21	TSEN54	TSEN54	RARS2	unknown
	TSEN54	TSEN34
	RARS2	TSEN2
References	[6–11]	[6, 7, 11, 12]	[11, 13, 14]	[7, 11, 12, 15]	[11, 16, 17]	[11, 18–20]	[11, 21]

In addition to the distinctive features reported in the table, microcephaly and intellectual disability are present in all types of PCH. AR: autosomal recessive

ISSN: 1750-1172