Turner 증후군 태아의 생존에 관한 세포유전학적 분석

Abstract

Background :The fact that the karyotypic abnormalities in patients with Turner syndrome can be diversely classified, and the high (above 95%) fetal loss rate of Turner karyotype has led to the suggestion that for survival of fetus with Turner syndrome, thereight be relatively favorable karyotype with minimal or less phenotypic effect. Method :To investigate the cytogenetic findings of Turner syndrome, we studied the 45 cases of liive-born with Turner syndrome (from peripheral blood among 2,087 cases with suspected chromosomal abnormalities) and the 11 cases of fetal loss(from 125 cases of passed conceptus, CVS or fetal tissue) in the period of Jan. 1991mMar. 1994. Result :The karyotypic abnormalities, in 11 cases of fetal loss with Turner syndrome, were classified as follows: 1) seven classic 45, X karyotype(63.6%), three mosaic 45, X/46, XX (27.3%) and one mosaic 45, x/45, XY (9.1%). In 45 cases of live-born with Turner syndrome, that were classified into seven groups; 1) 13 classic 45, X karyotype(28.9%), 2) one mosaic 45, X/46, m (2. 27;) , 3) four mosaic 45, IQ`47, Izm or other superfemale cell lines (8.9%), 4) 18 &chromosomes i (Xq) (40%)) 5) three ring chromosomes r(X) or r (mar) (6.7%) , 6) four other structural abnormalities of the X chromosomes (8.9%), and 7) two mosaic 45, X/46, XY (4.4%), and mosaicism with or without structural abnormalities was demonstrated in 15 of these patients(33.3%). Thus, in Turner syndrome, high incidence of classic 45, X karyotype in cases of fetal loss, and low incidence of classic 45, X karyotype and relatively high incidence of structural abnormalities and mosaicism of sex chromosome is noted. Conclusion :Above findings suggested that in Turner syndrome, structural abnormalities of sex-chromosome with or without mosaicism were more favorable karyotypes for survival of fetus than classic, 45, X karyotype. As sex-chromosome with structural abnormality, most of which might be disappeared during consecutive mitosis abnormality, could not be recognize in routine cytogenetic analysis, it seemed essential to be careful in cytogenetic analysis.