Lukusa T, Van Buggenhout G, Devriendt K, Fryns J P
Center for Human Genetics, University of Leuven, Belgium.
Genet Couns. 2002;13(1):1-10.
We report on a 29-year-old male patient with an inverted 7(q35-qter) duplication diagnosed by combining cytogenetic and FISH studies. Traditional G-banding detected an abnormally long chromosome 7 which was further demonstrated to be entirely of chromosome 7 origin by using fluorescent whole chromosome 7 painting. The presence within the additional segment of a signal for 7q36 region (Williams control probe) and the absence of signals for 7q33 (Y938G5 probe) and 7q34 (Y815G5 probe) regions indicated that the breakpoint for this rearrangement was distal to 7q34 and proximal to 7q36. A distal 7p22 deletion was confirmed by the absence of signal for the 7p subtelomeric probe. Apart from kyphosis, developmental/mental retardation and abnormal ears, the clinical features of the present patient, who is the oldest individual ever reported with this duplication/deletion, were not typical for partial 7q trisomy syndrome. A review of the cases reported with 7(q35-qter) duplication is made and shows important clinical variability but constantly normal pre- and postnatal growth, a feature which can therefore be confirmed as distinctive of distal 7q trisomy syndrome.
我们报告了一名29岁男性患者,通过细胞遗传学和荧光原位杂交(FISH)研究相结合诊断出7号染色体长臂(q35-qter)倒位重复。传统的G显带检测到一条异常长的7号染色体,通过使用7号全染色体荧光涂染进一步证实其完全源自7号染色体。在额外片段中存在7q36区域的信号(威廉姆斯对照探针),而7q33(Y938G5探针)和7q34(Y815G5探针)区域无信号,这表明该重排的断点位于7q34远端和7q36近端。7号染色体短臂末端(7p)探针无信号证实了7p22远端缺失。除了脊柱后凸、发育/智力迟缓及耳部异常外,该患者是有此重复/缺失报道中年龄最大的个体,其临床特征并非典型的部分7q三体综合征。本文对已报道的7(q35-qter)重复病例进行了综述,显示出重要的临床变异性,但出生前和出生后的生长始终正常,因此这一特征可确认为远端7q三体综合征的独特之处。