Fernhoff P M, Singh D N, Hanson J, Trusler S, Dumont C R, Chen A T
J Med Genet. 1976 Oct;13(5):389-93. doi: 10.1136/jmg.13.5.389.
Four families are described with a t(13q14q) segregating. Two of them were identified through index cases with Down's syndrome; their karotypes revealed the unusual 46,XY, -13, -14, +t(13q14q), +21. The other two families were identified through a chromosomal study of parents with repeated spontaneous abortions. Analysis of data on 3 of these 4 families and on 7 other from the published reports showed no evidence of increased fetal wastage among 13/14 carriers. However, the risk of producing offspring with various types of aneuploidy may be greater among carriers than among persons with a normal chromosome pattern. Qualitative and quantitative differences in D/D translocations may account for the observed variation in clinical findings. These differences add to the problem of determining genetic risks from an analysis of grouped data.
本文描述了四个伴有t(13q14q)分离的家系。其中两个家系是通过唐氏综合征的先证者确定的；他们的核型显示为异常的46,XY, -13, -14, +t(13q14q), +21。另外两个家系是通过对反复自然流产的父母进行染色体研究确定的。对这4个家系中的3个以及已发表报告中的其他7个家系的数据进行分析后发现，没有证据表明13/14携带者的胎儿丢失率增加。然而，携带者产生各种非整倍体后代的风险可能比染色体模式正常的人更大。D/D易位的定性和定量差异可能解释了观察到的临床结果差异。这些差异增加了通过分组数据分析确定遗传风险的问题。
