PARACENTRIC INVERSION OF A HUMAN CHROMOSOME-7

In the course of chromosome studies of atomic bomb survivors in Hiroshima using the trypsin-G-banding and Q-banding methods, a 40 yr old male had an abnormal banding pattern in the long arm of a chromosome 7, although no such abnormality was detected by ordinary staining method. Since all other chromosomes apparently had normal banding patterns, the abnormality was determined to be a paracentric inversion of a chromosome 7, which is described as 46,XY,inv(7)(q22q31). This is the 1st demonstration of a possible paracentric inversion in man.