Jacobsen Syndrome: Surgical Complications due to Unsuspected Diagnosis, the Importance of Molecular Studies in Patients with Craniosynostosis

Jacobsen syndrome (JBS) is an uncommon contiguous gene syndrome. About 85-92% of cases have a de novo origin. Clinical variability and severity probably depend on the size of the affected region. The typical clinical features in JBS include intellectual disability, growth retardation, craniofacial dysmorphism as well as craniosynostosis, congenital heart disease, and platelet abnormalities. The proband was a 1 year/3-month-old Mexican male. Oligonucleotide-SNP array analysis using the GeneChip Human Cytoscan HD was carried out for the patient from genomic DNA. The SNP array showed a 14.2-Mb deletion in chromosome 11q23.3q25 (120,706-134,938 Mb), which involved 163 RefSeq genes in the database of genomic variation. We report a novel deletion in JBS that increases the knowledge of the variability in the mutation sites in this region and expands the spectrum of molecular and clinical defects in this syndrome.