Biomedical subjects

Daniela del Gaudio

Publications and source records attributed to Daniela del Gaudio.

2 recordsLinked to original sources

PubMed2006

Prenatal diagnosis of chromosomal abnormalities using array-based comparative genomic hybridization.

PURPOSE: This study was designed to evaluate the feasibility of using a targeted array-CGH strategy for prenatal diagnosis of genomic imbalances in a clinical setting of current pregnancies. METHODS: Women undergoing prenatal diagnosis were counseled and offered array-CGH (BCM V4.0) in addition to routine chromosome analysis. Array-CGH was performed with DNA directly from amniotic fluid cells with whole genome amplification, on chorionic villus samples with amplification as necessary, and on cultured cells without amplification. RESULTS: Ninety-eight pregnancies (56 amniotic fluid and 42 CVS specimens) were studied with complete concordance between karyotype and array results, including 5 positive cases with chromosomal abnormalities. There was complete concordance of array results for direct and cultured cell analysis in 57 cases tested by both methods. In 12 cases, the array detected copy number variation requiring testing of parental samples for optimal interpretation. Array-CGH results were available in an average of 6 and 16 days for direct and cultured cells, respectively. Patient acceptance of array-CGH testing was 74%. CONCLUSION: This study demonstrates the feasibility of using array-CGH for prenatal diagnosis, including reliance on direct analysis without culturing cells. Use of array-CGH should increase the detection of abnormalities relative to the risk, and is an option for an enhanced level of screening for chromosomal abnormalities in high risk pregnancies.

Chromosome Aberrations↗

PubMed2006

Increased MECP2 gene copy number as the result of genomic duplication in neurodevelopmentally delayed males.

PURPOSE: Mutations in the MECP2 gene are associated with Rett syndrome, an X-linked mental retardation disorder in females. Mutations also cause variable neurodevelopmental phenotypes in rare affected males. Recent clinical testing for MECP2 gene rearrangements revealed that entire MECP2 gene duplication occurs in some males manifesting a progressive neurodevelopmental syndrome. METHODS: Clinical testing through quantitative DNA methods and chromosomal microarray analysis in our laboratories identified seven male patients with increased MECP2 gene copy number. RESULTS: Duplication of the entire MECP2 gene was found in six patients, and MECP2 triplication was found in one patient with the most severe phenotype. The Xq28 duplications observed in these males are unique and vary in size from approximately 200 kb to 2.2 Mb. Three of the mothers who were tested were asymptomatic duplication carriers with skewed X-inactivation. In silico analysis of the Xq28 flanking region showed numerous low-copy repeats with potential roles in recombination. CONCLUSIONS: These collective data suggest that increased MECP2 gene copy number is mainly responsible for the neurodevelopmental phenotypes in these males. These findings underscore the allelic and phenotypic heterogeneity associated with the MECP2 gene and highlight the value of molecular analysis for patient diagnosis, family members at risk, and genetic counseling.

Adolescent↗