Chromosome Aberrations in 2159 Consecutive Newborn Babies

Abstract

Preliminary results of chromosome studies on cultured umbilical-cord-blood leukocytes from a consecutive series of 2159 infants born during a year indicated that gross chromosome abnormalities were present in 0.48 per cent (cultures were successful in 1066 males and 1015 females, representing 96.3 per cent ascertainment). These included four infants with XYY, one with XXY and one with D/D translocation trisomy (all male), as well as two with regular trisomy 21, one with D/D balanced translocation and one with cri du chat (all female). These results suggest that D/D translocation heterozygosis will be found in random human populations with a rate of at least 1 in 1000 and probably represents the most frequent type of chromosomal rearrangement. The XYY condition appears in the order of 1 in 250 males. This may represent the most common form of aneuploidy in human beings.