A CHROMOSOME SURVEY OF UNSELECTED LIVE-BORN CHILDREN WITH CONGENITAL ABNORMALITIES

Twenty-five hundred consecutive live-born babies, 1,264 males and 1,236 females, have been examined clinically and for nuclear sex. Chromosome studies were carried out on the 184 (7.4 per cent) infants judged to have a congenital physical abnormality. Of these, 8 had an abnormal karyotype (4.3 per cent) including 2 males with a 47, XXY complement, 1 female with a 47, XXX complement, 3 with mongolism (47, XY, 21+), and 2 with reciprocal translocations. In addition, 3 babies among the 2,316 who had no detectable physical abnormality were found to have an abnormal nuclear sex. There were 2 chromatin positive males, 1 with a 47, XXY complement and 1 with a 46, XX complement, and 1 chromatin negative female with a 45, X/46, XXr complement. These findings are discussed, as is the contribution of chromosomal abnormalities detectable in mitotic cells to the ctiology of congenital physical abnormalities. © 1969 The C. V. Mosby Company.