Hereditary Spastic Paraplegia - paediatric
Gene: INPP4A
PMID: 39315527
30 individuals (aged 6 months to 40 years) from 17 unrelated families with biallelic LOF variants in INPP4A gene (11 nonsense or frameshift and 3 missense, mostly exon 4).
Cardinal clinical features include: severe global developmental delay, profound speech impairment, severe-profound intellectual disability, and severe lower limb weakness/paralysis. More variable clinical features include: microcephaly, short stature, cerebellar signs, involuntary movements, axial hypotonia, spasticity, quadriparesis, joint contractures, seizures, visual impairment. Neuroimaging findings vary from normal to features of (ponto)cerebellar hypoplasia, ventriculomegaly, reduced cerebral volume and hypomyelination. A more severe presentation is seen with variants downstream of exon 4.
Preliminary fibroblast cell studies identify disruption of endocytic pathways as the likely mechanism of disease, consistent with previous findings of a role of INPP4A in endocytosis. All mouse models display a phenotype mirroring human INPP4A-related neurodevelopmental disorder entailing a severe movement disorder with inability to walk, a small brain, and poor growth/weight gain.
Sources: LiteratureCreated: 16 Jan 2025, 4:27 a.m.
Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal
Phenotypes
INPP4A-related neurodevelopmental disorder
Publications
Gene: inpp4a has been classified as Green List (High Evidence).
gene: INPP4A was added gene: INPP4A was added to Hereditary Spastic Paraplegia - paediatric. Sources: Literature Mode of inheritance for gene: INPP4A was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: INPP4A were set to PMID: 39315527 Phenotypes for gene: INPP4A were set to INPP4A-related neurodevelopmental disorder Review for gene: INPP4A was set to GREEN