White matter disorders and cerebral calcification - narrow panel
Gene: USP18
Added 'treatable' tag as clinical remission was achieved in a patient following rapid genetic diagnosis and subsequent treatment with the JAK inhibitor ruxolitinibCreated: 8 Oct 2020, 4:05 p.m. | Last Modified: 8 Oct 2020, 4:05 p.m.
Panel Version: 1.18
- PMID: 27325888 (2016) - Three sibs from a consanguineous Turkish family with a homozygous variant (c.652C>T, p.Q218X) in USP18. Antenatal presentation in one sib led to termination of pregnancy at 22 wk of gestation, and in the remaining two children presentation was neonatal and resulted in death within 2 weeks of life. In the latter two individuals manifestations included severe intracerebral haemorrhages, liver dysfunction, ascites, and lactic acidosis. One sib additionally had severe thrombocytopenia with petechiae, while the other developed seizures.
Two German sibs, previously reported in PMID: 12833411 (2013), were found to be compound het for the same p.Q218X variant and a cryptic 3-prime deletion of the USP18 gene. They presented thrombocytopenia, petechiae, ascites, hepatomegaly, and systemic calcifications. Within the first days of life, they developed seizures and died from severe cerebral haemorrhage.
Haplotype analysis of the region containing the Q218X mutation suggested a common ancestor between the 2 families and a founder effect.
- PMID: 31940699 (2020) - One Saudi Arabian boy with a homozygous splice-site variant (c.1073+1G>A) in USP18, presented hydrocephalus with seizures, intraventricular haemorrhage, brain calcifications, necrotizing cellulitis, systemic inflammation, multiple organ failure, and respiratory failure. This was the only patient to survive beyond the perinatal period owing to supportive care and prompt treatment with ruxolitinib. At the time of publication, the child was 3-years-old and was in full remission of clinical manifestations while continuing to receive oral ruxolitinib. He continues to grow normally, however authors note delay in developmental milestones.Created: 8 Oct 2020, 4:05 p.m. | Last Modified: 8 Oct 2020, 4:05 p.m.
Panel Version: 1.18
Mode of inheritance
BIALLELIC, autosomal or pseudoautosomal
Phenotypes
Pseudo-TORCH syndrome 2, 617397
Publications
Publications for gene: USP18 were set to PMID: 27325888
Phenotypes for gene: USP18 were changed from pseudo-TORCH syndrome to Pseudo-TORCH syndrome 2, 617397
Tag treatable tag was added to gene: USP18.
Checked against super panel made up of the panel constituents. Ready to promote to version 1
gene: USP18 was added gene: USP18 was added to White matter disorders and cerebral calcification - narrow panel. Sources: Expert Review Green Mode of inheritance for gene: USP18 was set to BIALLELIC, autosomal or pseudoautosomal Publications for gene: USP18 were set to PMID: 27325888 Phenotypes for gene: USP18 were set to pseudo-TORCH syndrome