Cotter P D, Caggana M, Willner J P, Babu A, Desnick R J
Department of Human Genetics Mount Sinai School of Medicine, New York, NY 10029, USA.
Am J Med Genet. 1996 Dec 11;66(2):197-9. doi: 10.1002/(SICI)1096-8628(19961211)66:2<197::AID-AJMG14>3.0.CO;2-O.
Two apparently balanced chromosome rearrangements were identified in a 17-week fetus by analysis of cultured amniocytes. The fetal karyotype was 46,XX,t(2;16) (q33;q24), inv(7)(p15q11.23). Parental karyotypes were normal, indicating a de novo origin of both chromosome rearrangements in the fetus. The risk of phenotypic abnormality from a de novo reciprocal translocation of inversion has been estimated at approximately 7% [Warburton, 1991]. The risk of abnormality in this fetus was estimated to be a minimum of 14%, based on the additive risk of each rearrangement, equivalent to 3.5% per chromosome breakpoint. The pregnancy was terminated because of the risk of abnormality and the detection of intrauterine growth retardation by ultrasound. In the absence of additional experience, the minimum presumed risk of phenotypic abnormality for de novo, multiple or complex chromosome rearrangements identified prenatally may be estimated as the additive risk of the number of chromosome breakpoints involved.
通过对培养的羊水细胞进行分析，在一名17周大的胎儿中发现了两种明显平衡的染色体重排。胎儿核型为46,XX,t(2;16)(q33;q24), inv(7)(p15q11.23)。父母核型正常，表明胎儿的这两种染色体重排均为新发。新发相互易位或倒位导致表型异常的风险估计约为7%[沃伯顿，1991]。根据每种重排的累加风险，该胎儿的异常风险估计至少为14%，相当于每个染色体断点3.5%。由于存在异常风险且超声检查发现胎儿宫内生长受限，该妊娠被终止。在缺乏更多经验的情况下，产前发现的新发、多发或复杂染色体重排的最低假定表型异常风险可估计为所涉及染色体断点数量的累加风险。
