FREQUENCY OF CHROMOSOME VARIANTS IN HUMAN-POPULATIONS

  • 1 January 1979
    • journal article
    • research article
    • Vol. 15  (4) , 745-751
Abstract
Chromosome variants were analyzed in the course of a population chromosome investigation of 6000 newborns and clinical cytogenetic studies of 403 married couples with recurrent spontaneous abortions, stillbirths or offspring with congenital malformations or Down''s syndrome. The total frequency of variants in newborns was 12.8/1000 births. The incidence of different types of variants per 1000 births was as follows: 1gh+ -0.33; 9gh+ -0.17; 16gh+ -0.50; Ds+ -2.33; Dp+ -1.50; Dp- -0.17; Gs+ -0.83; Gp+ -2.17; Yq+ -6.91/1000 males; Yg- -0.99/1000 males; double variants -0.33; other variants -0.33. About 4.0% of married couples with recurrent spontaneous abortions had major chromosome aberrations and 14.6% had chromosome variants. Among 113 couples with a history of congenitally malformed offspring, major chromosome abnormalities were found in 4.4%, and chromosome variants in 13.3%. The frequency of chromosome variants among 139 patients with Down''s syndrome was 7.2%. In 1 case a Robertsonian translocation t(DqGq) was seen. The most frequent types of variant chromosomes were Ds+, Dp+, Es+, Yq+.