Hachiro Shimba

A chromosome survey of induced abortuses in a Japanese population.

Chromosomal studies were carried out on either cultured or noncultured embryonic tissues derived from 140 cases of induced abortuses which were randomly collected in Sapporo during a period from January, 1963 to April, 1966. The mean maternal age for this series was 27.5±5.8 (S.D.) years, and the mean gestational age was 9.6±3.1 (S.D.) weeks. Among the cases, 133 were found to have a normal chromosome constitution of either male (46-XY) or female (46-XX), with a sex-ratio of 83♀∶50♂. Seven cases were chromosomally abnormal: They were 3 mosaic cases with 45-XO/46-XY, 46-XY/47-XXY and 45-XO/46-XX karyotypes, 1 case of X-monosomy with the 45-XO karyotype, 1 case of X-trisomy with the 47-XXX karyotype, a male with an unusually long Y chromosome, and a female showing a high incidence of chromosome breakage. A high incidence of chromosome abnormalities was obtained in association, within a limited period, of epidemics for three viral diseases.