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Updated: Jul 18, 2026

Spectral Karyotyping to Study Chromosome Abnormalities in Humans and Mice with Polycystic Kidney Disease
Published on: February 3, 2012
Chromosome Y polysomy: a non-mosaic 49,XYYYY case
Ariane Paoloni-Giacobino1, James Lespinasse
1Department of Molecular Genetics and Biochemistry, Pittsburgh University, Pennsylvania, USA Cytogenetic Laboratory, General Hospital, Chambéry Cedex, France.
Abstract:
Karyotypic abnormalities involving the Y chromosome are common. The clinical spectrum associated with Y chromosome trisomy, tetrasomy or pentasomy is imprecise, as still very few cases have been reported. All cases, however, seem to exhibit some degree of mental retardation and minor facial dysmorphisms. The case we describe is only the fifth reported case of non-mosaic Y tetrasomy. This report and follow-up of a patient, between 4 months and 26 years of age, will certainly be helpful in better characterizing this karyotypic defect.
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