Clinical-Neurological, cytogenetic and molecular aspects of Prader-Willi and Angelman syndromes

The Prader-Willi syndrome (PWS) and the Angelman syndrome (AS) are human neurogenetic disorders involving the imprinting mechanism, at the 15q11-13 chromosome region. The predominant genetic defects in PW are 15q 11-13 deletions of paternal origin and maternal chromosome 15 uniparental disomy. In contrast, maternal deletions and paternal chromosome 15 uniparental disomy are associated with a different neurogenetic disorder, the AS. In both disorders, these mutations are associated with parent-of-origin specific methylation at several 15q 11-13 loci. We studied 5 patients suspect of PWS and 4 patients suspect of AS who were referred to the Medical Genetics Unit at the University Hospital of Medical School from Ribeirão Preto. Our objective was to establish the correct clinical and etiological diagnosis in these cases. We used conventional cytogenetics, methylation analysis with the probe KB 17 (CpG island of the SNRPN gene) by Southern blotting after digestion with the Xba I and Not I restriction enzymes. We studied in patients and their parents the segregation of the (CA)n repeats polymorphisms by PCR, using the primers 196 and IR4-3R. All the patients had normal conventional cytogenetical analysis. We confirmed 3 cases of PWS: one by de novo deletion, one by maternal chromosome 15 uniparental disomy and one case with no defined cause determined by the used primers. We confirmed 2 cases of AS, caused by de novo deletion at the 15q 11-13 region, and one case with normal molecular analysis but with strong clinical characteristics

Cherubism Combined with Epilepsy, Mental Retardation and Gingival Fibromatosis (Ramon Syndrome): A Case Report

Cherubism is an inherited, autosomal dominant disorder that characteristically affects the jaws of children. The disease typically manifest as a bilateral swelling with associated submandibular lymph node enlargements and usually regresses as age advances. The disease is microscopically indistinguishable from other giant cell lesions and is essentially a clinical diagnosis. The association of cherubism with gingival fibromatosis, epilepsy, mental retardation, stunted growth, and hypertrichosis is referred as Ramon syndrome. We report a case of Ramon syndrome in an 8 year old girl

Genetic counseling for individuals with hemoglobin disorders and for their relatives: a systematic literature review

Objective: To identify genetic counseling programs that do not encourage therapeutic abortion for individuals with hemoglobin disorders and/or for their relatives. Method: Systematic literature review of articles published from 2001 to 2012 that are located in the PubMed, LILACS, SciELO and SCOPUS databases using keywords in Portuguese, English and Spanish and that met the inclusion and exclusion criteria described on a standardized form. Results: A total of 409 articles were located, but only eight (1.9%) were selected for analysis. Conclusion: Although seldom mentioned in the literature, educational/preventive programs targeting hemoglobinopathies are feasible and allow the affected individuals to acquire knowledge on the consequences of this condition and their odds of transmitting it

Jaffe-Campanacci syndrome, revisited: detailed clinical and molecular analyses determine whether patients have neurofibromatosis type 1, coincidental manifestations, or a distinct disorder

Purpose: "Jaffe-Campanacci syndrome" describes the complex of multiple nonossifying fibromas of the long bones, mandibular giant cell lesions, and cafe-au-lait macules in individuals without neurofibromas. We sought to determine whether Jaffe-Campanacci syndrome is a distinct genetic entity or a variant of neurofibromatosis type 1. Methods: We performed germline NF1, SPRED1, and GNAS1 (exon 8) mutation testing on patients with Jaffe-Cainpanacci syndrome of Jaffe-Campanacci syndrome-related features, We also performed somatic NF1 mutation testing on nonossifying fibromas and giant, cell lesions. Results: Pathogenic germline NF1 mutations Were identified 13 of 14 patients with multiple cafe-au-lait macules and niultiple non-ossifying fibromas or giant cell lesions ("classicar Jaffe-Campanacci syndrome); all 13 also fulfilled the National Institues of Health diagnostic criteria for neurofibromatosis type 1. Somatic NFI mutations were detected in two giant cell lesions but not in two nonossifying fibromas. No SPRED1 or GNAS1 (exon 8) mutations were detected in the seven NF1-negative patients with Jaffe-Campanacci syndrome, nonossifying fibromas, or giant cell lesions. Conclusion: In this study, the majority of patients with cafe-au-lait macules and nonossifying fibromas Or giant cell lesions harbored a pathogenic gerinline NF1 mutation,suggesting that many Jaffe-Campanacci syndrome cases may-actually have neurofibromatosis type 1. We provide the first proof of specific somatic second-hit mutations affecting NFI in two giant cell lesions from two unrelated patients, establishing these as neurofibromatosis type 1-associated tumors