RESUMO
Williams-Beuren syndrome (WBS) is a multisystemic genomic disorder typically caused by a recurrent Ë1.5-1.8 Mb deletion on 7q11.23. Atypical deletions can provide important insight into the genotype-phenotype correlations. Here, we report the phenotypic and molecular characterization of a girl with a de novo 81.8 kb deletion in the WBS critical region, which involves the ELN and LIMK1 genes only. The patient presented at 2 months of age with extensive vascular abnormalities, mild facial dysmorphism and delays in her fine motor skills. We discuss potential molecular mechanisms and the role of ELN and LIMK1 in the different phenotypic features. We compare the findings in our patient with previously reported overlapping deletions. The phenotypic variability among these patients suggests that other factors are important in the phenotype and possibly include: position effects related to copy number variation size, variations in the non-deleted alleles, genetic modifiers elsewhere in the genome, or reduced penetrance for specific phenotypes.
Assuntos
Estudos de Associação Genética , Síndrome de Williams/genética , Síndrome de Williams/patologia , Sequência de Bases , Quebra Cromossômica , Cromossomos Humanos/genética , Hibridização Genômica Comparativa , Feminino , Deleção de Genes , Humanos , Hibridização in Situ Fluorescente , Lactente , Recém-Nascido , Masculino , Dados de Sequência Molecular , Análise de Sequência com Séries de Oligonucleotídeos , Análise de Sequência de DNARESUMO
The neutron elastic magnetic form factor was extracted from quasielastic electron scattering on deuterium over the range Q;{2}=1.0-4.8 GeV2 with the CLAS detector at Jefferson Lab. High precision was achieved with a ratio technique and a simultaneous in situ calibration of the neutron detection efficiency. Neutrons were detected with electromagnetic calorimeters and time-of-flight scintillators at two beam energies. The dipole parametrization gives a good description of the data.