Multiple small accessory marker chromosomes from different centromeric origin in a moderately mentally retarded male.

J R Vermeesch; H Duhamel; P Petit; D Falzetti; J P Fryns; P Marynen

doi:10.1007/s004399900184

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Multiple small accessory marker chromosomes from different centromeric origin in a moderately mentally retarded male.

J R Vermeesch·H Duhamel·P Petit·D Falzetti·J P Fryns·P Marynen

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Abstract

The occurrence of more than two small accessory chromosomes (SACs) in a single individual is extremely rare. Here, we characterize six SACs found in the cells of two different tissues of a moderately mentally retarded male. Microdissection combined with regular FISH demonstrates that the SACs are ring chromosomes derived from the centromeres of different chromosomes. The SACs are often associated with the centromeres of other chromosomes. Immunofluorescence with an anti-CENP-C antibody demonstrates that the SACs contain an active centromere. A possible mechanism by which the SACs originated and their clinical relevance are discussed.

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Centromere Chromosomes, Human, Pair 12 Fluorescent Antibody Technique Humans In Situ Hybridization, Fluorescence Intellectual Disability Karyotyping Male Middle Aged Polymerase Chain Reaction Ring Chromosomes Case Reports Journal Article Research Support, Non-U.S. Gov't

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J R Vermeesch, H Duhamel, P Petit, D Falzetti, J P Fryns, P Marynen. 1999. Multiple small accessory marker chromosomes from different centromeric origin in a moderately mentally retarded male.. https://doi.org/10.1007/s004399900184

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