Stable dicentric autosome, tdic (8:22)(p23:p13), in a mentally retarded girl.

A new stable human dicentric chromosome, tdic(4;21)(p16;q22), in a woman with first trimester abortion.

A woman with first trimester abortion and a dicentric chromosome formed from a 4 and a 21 is described. The dicentric chromosome was stable and in the majority of cells the 21 centromere was active, while in a minority the chromosome 4 centromere was active. This shows that both centromeres were functional, but that only one functioned in any given cell. Suppression of the activity of one centr...

Anomalies of development in a girl with unusual sex chromosomal mosaicism.

Morphological abnormalities of the X chromosome are well documented and have been extensively reviewed and discussed by Ferguson-Smith (1965). They include isochromosome of the long arm, deletions of the long and short arms, ring chromosomes, and chromosomal fragments. Other types of abnormality are rare. Engel and Forbes (1965) described a chromatin negative girl (Patient No. 27) with a mosaic...

Development in a Girl with Unusual Sex Chromosomal Mosaicism

Morphological abnormalities of the X chromosome are well documented and have been extensively reviewed and discussed by Ferguson-Smith (1965). They include isochromosome of the long arm, deletions of the long and short arms, ring chromosomes, and chromosomal fragments. Other types of abnormality are rare. Engel and Forbes (1965) described a chromatin negative girl (Patient No. 27) with a mosaic...

An extra small metacentric autosome in a mentally retarded boy with multiple malformations.

Sex Chromosomal Mosaicism

Morphological abnormalities of the X chromosome are well documented and have been extensively reviewed and discussed by Ferguson-Smith (1965). They include isochromosome of the long arm, deletions of the long and short arms, ring chromosomes, and chromosomal fragments. Other types of abnormality are rare. Engel and Forbes (1965) described a chromatin negative girl (Patient No. 27) with a mosaic...