Cytogenetic observations in cultured lymphocytes from patients with down’s syndrome and measles

Abstract

Chromosomes were studied in 72-hr lymphocyte cultures from 11 patients with Down’s syndrome and 8 hematologically and karyotypically normal control subjects before and after measles infection. The number of breaks per cell in patients with Down’s syndrome after measles infection was 0.191 d= 0.073, which was significantly greater than the number of breaks before infection (0.040 ± 0.020) and which was also significantly greater than the number of breaks in control children with measles (0.046 ± 0.024). Therefore, chromosomes of cells of patients with Down’s syndrome were significantly more sensitive to measles infection than those of control subjects. Statistical assessments were made on randomness and nonrandomness of breakage distribution in chromosome groups and arms. Excess breaks were found to occur in the long arms of B and D group chromosomes. Patients with Down’s syndrome show more chromosomal breaks after virus infection than do normal control subjects. The susceptibility of patients with Down’s syndrome to neoplasia may allow us to recognize trisomic cells to be particularly cancer prone. © 1973 International Pediatric Research Foundation, Inc.