title: Skewed X chromosome inactivation and trisomic spontaneous abortion: no association.
abstract: Several studies suggest that highly skewed X chromosome inactivation (HSXI) is associated with recurrent spontaneous abortion. We hypothesized that this association reflects an increased rate of trisomic conceptions due to anomalies on the X chromosome that lead both to HSXI and to a diminished oocyte pool. We compared the distribution of X chromosome inactivation (XCI) skewing percentages (range: 50%-100%) among women with spontaneous abortions in four karyotype groups-trisomy (n = 154), chromosomally normal male (n = 43), chromosomally normal female (n = 38), nontrisomic chromosomally abnormal (n = 61)-to the distribution for age-matched controls with chromosomally normal births (n = 388). In secondary analyses, we subdivided the nontrisomic chromosomally abnormal group, divided trisomies by chromosome, and classified women by reproductive history. Our data support neither an association of HSXI with all trisomies nor an association of HSXI with chromosomally normal male spontaneous abortions. We also find no association between HSXI and recurrent abortion (n = 45).
authors: Department of Genetics and Development, Columbia University, New York, NY 10032, USA. dw9@columbia.edu
authors: Dorothy
authors: D
authors: Warburton
authors: Jennie
authors: J
authors: Kline
authors: Ann
authors: A
authors: Kinney
authors: Chih-Yu
authors: CY
authors: Yu
authors: Bruce
authors: B
authors: Levin
authors: Stephen
authors: S
authors: Brown
mesh_terms: D000026:Abortion, Habitual / Q000235:genetics*; D000022:Abortion, Spontaneous / Q000235:genetics*; D016022:Case-Control Studies; D041321:Chromosomes, Human, X; D005260:Female; D006801:Humans; D007621:Karyotyping; D008297:Male; D011247:Pregnancy; D018570:Risk Assessment; D014314:Trisomy; D049951:X Chromosome Inactivation