Molecular Cytogenetics · 2008 · 31 citations · 16 references
Life SciencesGeneticsMolecular GeneticsCytogeneticsHuman GeneticsMedical GeneticsChromosomal AbnormalitiesChromosomal DisordersComparative Genomic HybridizationMolecular CytogeneticsNumerical Chromosome AbnormalitiesStructural Chromosome AbnormalitiesArray Comparative Genomic HybridizationArray Genomic HybridizationComplex Chromosome RearrangementsDerivative ChromosomesDna In Situ HybridizationMolecular Cytogenetic DiagnosisSmall Supernumerary Marker Chromosomes
BACKGROUND: Small supernumerary marker chromosomes (sSMC) are present ~2.6 x 106 human worldwide. sSMC are a heterogeneous group of derivative chromosomes concerning their clinical consequences as well as their chromosomal origin and shape. Besides the sSMC present in Emanuel syndrome, i.e. der(22)t(11;22)(q23;q11), only few so-called complex sSMC are reported. RESULTS: Here we report three new cases of unique complex sSMC. One was a de novo case with a dic(13 or 21;22) and two were maternally derived: a der(18)t(8;18) and a der(13 or 21)t(13 or 21;18). Thus, in summary, now 22 cases of unique complex sSMC are available in the literature. However, this special kind of sSMC might be under-diagnosed among sSMC-carriers. CONCLUSION: More comprehensive characterization of sSMC and approaches like reverse fluorescence in situ hybridization (FISH) or array based comparative genomic hybridization (array-CGH) might identify them to be more frequent than only ~0.9% among all sSMC.
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