Dataset Information

Brain calcifications and PCDH12 variants.

ABSTRACT:

Objective

To assess the potential connection between PCDH12 and brain calcifications in a patient carrying a homozygous nonsense variant in PCDH12 and in adult patients with brain calcifications.

Methods

We performed a CT scan in 1 child with a homozygous PCDH12 nonsense variant. We screened DNA samples from 53 patients with primary familial brain calcification (PFBC) and 26 patients with brain calcification of unknown cause (BCUC).

Results

We identified brain calcifications in subcortical and perithalamic regions in the patient with a homozygous PCDH12 nonsense variant. The calcification pattern was different from what has been observed in PFBC and more similar to what is described in in utero infections. In patients with PFBC or BCUC, we found no protein-truncating variant and 3 rare (minor allele frequency <0.001) PCDH12 predicted damaging missense heterozygous variants in 3 unrelated patients, albeit with no segregation data available.

Conclusions

Brain calcifications should be added to the phenotypic spectrum associated with PCDH12 biallelic loss of function, in the context of severe cerebral developmental abnormalities. A putative role for PCDH12 variants remains to be determined in PFBC.

SUBMITTER: Nicolas G

PROVIDER: S-EPMC5530423 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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Publications

Brain calcifications and <i>PCDH12</i> variants.

Nicolas Gaël G Sanchez-Contreras Monica M Ramos Eliana Marisa EM Lemos Roberta R RR Ferreira Joana J Moura Denis D Sobrido Maria J MJ Richard Anne-Claire AC Lopez Alma Rosa AR Legati Andrea A Deleuze Jean-François JF Boland Anne A Quenez Olivier O Krystkowiak Pierre P Favrole Pascal P Geschwind Daniel H DH Aran Adi A Segel Reeval R Levy-Lahad Ephrat E Dickson Dennis W DW Coppola Giovanni G Rademakers Rosa R de Oliveira João R M JRM

Neurology. Genetics 20170726 4

<h4>Objective</h4>To assess the potential connection between PCDH12 and brain calcifications in a patient carrying a homozygous nonsense variant in <i>PCDH12</i> and in adult patients with brain calcifications.<h4>Methods</h4>We performed a CT scan in 1 child with a homozygous <i>PCDH12</i> nonsense variant. We screened DNA samples from 53 patients with primary familial brain calcification (PFBC) and 26 patients with brain calcification of unknown cause (BCUC).<h4>Results</h4>We identified brain ...[more]

PMID: 28804758

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