Prior studies have shown that short stature, and cognitive and lymphoedema traits in TS are correlated with Xp deletions.
Turner syndrome pdf info software#
Results were analysed using CGH Analytics V.3.4 software from Agilent. 9, 10 Further characterisation of X chromosome deletion breakpoints for informative cases was on genomic DNA isolated from whole blood and analysed by comparative genomic hybridisation using custom X chromosome tiling arrays containing 220 000 probes with average 280 bp spacing (Agilent Technology). 11 The diagnosis of BAV, COA, and anomalous pulmonary veins (APV) by cardiac MRI has been described in prior papers. The review of 50 metaphases rules out mosaicism for a second cell line with 95% confidence. Inclusion in this CHD focused sub-study required a peripheral blood karyotype with 100% of cells in 50-metaphase analyses demonstrating (1) 45X (2) 46,X,del(Xp) (3) 46,X,i(Xq) (45) 46,X,del(Xq), and ability to undergo a cardiac MRI. Participants or parents in the case of minors signed institution review board approved informed consent documents. Study subjects were enrolled in the intramural NICHD (National Institute of Child Health and Human Development) protocol: Turner syndrome: genotype and phenotype (NCT:00006334). Therefore, in the present study we investigated the prevalence of CHD in groups of girls and women with non-mosaic karyotypes for 45,X compared to prevalence in groups with selective deletions of X chromosome short or long arms. 7 The most common cardiovascular defects in surviving girls and women are bicuspid aortic valve (BAV) and aortic coarctation (COA), seen in approximately 30% and 12%, respectively, 8–10 but the chromosomal locus for CHD in TS has not been established. 6 Approximately 10% of newborns with TS have left heart hypoplasia, which is usually lethal. 5Ĭongenital heart defects (CHD) are a major cause of pre- and postnatal mortality in TS.
5 Second trimester miscarriages are associated with severe fetal hydrops, and defective lymphatic and vascular development. 4 Most spontaneous 45,X abortions occur in mid-late first trimester characterised by ruptured chorionic and amniotic sacs and minimal fetal development. 3 The cause for this high rate of lethality in human gestations is unknown, and contrasts with the fact that X monosomy does not impair survival, somatic size or fertility in mice. 1, 2 Although formation of embryos monosomic for the X chromosome occurs commonly during mammalian reproduction, the great majority of human 45,X gestations are lost in spontaneous abortions. Turner syndrome (TS) is caused by sex chromosome haploinsufficiency and occurs in ∼1/2500 live female births, as determined by large-scale cytogenetic screening studies.
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