September 1974

A Child With a Ring-4 Chromosome (46,XX/46,XX,r 4)

Author Affiliations

From the divisions of child development (Dr. Parker) and medical genetics (Drs. Alfi and Donnell and Ms. Derencsenyi), Children's Hospital of Los Angeles, and the University of Southern California School of Medicine (Los Angeles); and the Department of Anthropology (Dr. Mavalwala), University of Toronto.

Am J Dis Child. 1974;128(3):371-374. doi:10.1001/archpedi.1974.02110280101015

A 10-year-old mentally and physically retarded girl has a mosaic ring-4 chromosome. The number of ring chromosomes in her peripheral blood preparations has increased from 9% to 72% in the past seven years. The child had a low birth weight and has had several phenotypic changes.