Cytogenetical study and analysis on 2083 cases of genetic counseling in Guizhou

Objective:To study and analyze cytogenetics of 2 083 cases of genetic counseling in Guizhou.Methods:The cases received conventional medical history inquiry and physical examination,1.5 milliliters venous blood were taken for lymphocyte culture,metaphase chromosome preparation section,G-banding technique was performed;30 karyotypes were counted under microscope for each case,more than 3 karyotypes were analyzed,the count and analytical dose were increased for the cases with abnormal results,naming was performed according to ISCN(1985).Results:Among 2 083 cases of genetic counseling,840 cases had the history of abnormal pregnancy,631 cases were infertile,108 cases suffered from sexual abnormality,90 cases had primary amenorrhea,241 cases had children with mental retardation,173 cases received birth health counseling before pregnancy,1 954 cases were found with normal chromosomal karyotype,and 129 cases(6.19%) were found with abnormal chromosomal karyotype,including 47 cases of loss of fetus during pregnancy,27 infertile cases,13 cases of sexual abnormality,11 cases of primary amenorrhea,29 cases with mental retardation children and 2 cases receiving birth health counseling before pregnancy.Conclusion:The history of abnormal pregnancy and infertility are the most common causes of genetic counseling,the main type of chromosomal abnormalities is balanced translocation;for the cases with sexual abnormality,dysplasia of secondary sexual characteristics is the main reason of visiting hospital,the main abnormal chromosomal karyotype is 47,XXY.Most of the cases with primary amenorrhea are Turner syndrome;most of the children with mental retardation suffer from 21-trisomy;publicizing and spreading birth health genetic counseling before pregnancy actively,understanding chromosomal abnormalities timely and participating in prenatal diagnosis may give birth to healthy offsprings selectively.