Meiotic outcomes of three-way translocations ascertained in cleavage-stage embryos: refinement of reproductive risks and implications for PGD

摘要: Our study provides an analysis of the outcome meiotic segregation three-way translocations in cleavage-stage embryos and accuracy limitations preimplantation genetic diagnosis (PGD) using fluorescence situ hybridization technique. We propose a general model for estimating reproductive risks carriers this class complex chromosome rearrangement. The data presented describe six cycles four couples where one partner has translocation. For male heterozygotes, 27.6% were consistent with 3:3 alternate resulting normal or balanced translocation complement; 41.4% adjacent translocations, comprising 6.9% reflecting adjacent-1 34.5% adjacent-2 segregation; 24.1% 4:2 nondisjunction; none showed 5:1 6:0 probable mode could not be ascertained due to mosaicism nucleus fragmentation. test heterozygotes was estimated 93.1% 100% sensitivity 75% specificity. With 72.4% prevalence, predictive value 91.3% abnormal result result. Two had healthy baby following PGD. proportion normal/balanced embryo significantly less female our indicates that detrimental effectiveness A 20% risk live-born offspring unbalanced is generally accepted, largely based on obstetric history heterozygotes; we suggest 3% may more appropriate carriers.