Cytogenetic evaluation of 500 Jerusalem newborn infants.

Cytogenetic investigations were carried out on cord blood lymphocytes of 500 normal healthy newborns. This population was divided into seven geoethnic groups according to the birthplace of the four grandparents of the infant. No numerical chromosomal aberrations were observed, but 10% of the individuals manifested cytogenetic variants. Six inherited structural abnormalities (four inversions and two deletions) were observed, while the remainder were classified as "minor variants." The chromosomal variants were randomly distributed among the population, and no particular variant was characteristic of a given subgroup.