Brain abnormalities in Cri-du-Chat syndrome – MRI findings

Brain Abnormalities in Cri-du-Chat syndrome – MRI findings.

Chromosome 5

The clinical manifestations of cri-du-chat syndrome are well known. Previous studies have revealed segments of chromosome 5p responsible for the cat-like cry, growth delay, microcephaly, etc. Structural brain anomalies detected by magnetic resonance imaging (MRI) have not been specifically investigated on a large cohort of patients. The authors of this new publication report on the results of MRIs in 14 patients with this condition. Four of these patients had an additional imbalance of other chromosomes.

The study showed hypoplastic pons in all but one patient. Hypoplastic cerebellar vermis was found in 8 patients. The corpus callosum (CC) was normal only in 3 patients, others had “dysmorphic” CC. Complete agenesis of the CC was reported only in 1 child. Polymicrogyria was revealed in 5 patients. A comparison of morphological brain defects and deleted segments of 5p showed that the minimal region of overlap for the hypoplastic pons was ~9.6 Mb (from the position 2.1 Mb to 11.7 Mb), this region includes at least 20 genes. The minimal region of overlap for vermian hypoplasia is only 2.4 Mb (from position 11.7 Mb to 14.1 Mb). This segment includes only 2 genes (TRIO and DNAH5), both these genes may be responsible for development of the cerebellar vermis. Polymicrogyria may be caused by deletions of the more proximal segment of 5p (from 14.2 Mb to 18.2 Mb) and includes MYO10 and BASP1 genes, which (when deleted) may lead to this defect.

Further examinations of a large cohort of patients may be necessary to determine genotype-brain phenotype correlations.

Villa R. et al. “Structural brain anomalies in Cri-du-Chat syndrome: MRI findings in 14 patients and possible genotype-phenotype correlations”. “Eur. J. Paed. Neurology” 2020, v. 28, 110-119.

This is a synopsis of a newly published research article. Important new research articles are selected by Dr. Iosif Lurie, M.D. Ph.D for addition to these pages. For more information on any article please contact info@chromodisorder.org