Estabrooks L L, Lamb A N, Kirkman H N, Callanan N P, Rao K W
Department of Pediatrics, University of North Carolina, Chapel Hill 27599.
Am J Hum Genet. 1992 Nov;51(5):971-8.
We report two families with a satellited chromosome 4 short arm (4ps). Satellites and stalks normally occur on the short arms of acrocentric chromosomes; however, the literature cites several reports of satellited nonacrocentric chromosomes, which presumably result from a translocation with an acrocentric chromosome. This is the first report of 4ps chromosomes. Our families are remarkable in that both unaffected and affected individuals carry the 4ps chromosome. The phenotypes observed in affected individuals, although dissimilar, were sufficient to encourage a search for a deletion of chromosome 4p. By Southern blot analysis and fluorescence in situ hybridization, a deletion of material mapping approximately 150 kb from chromosome 4pter was discovered. This deletion is notable because it does not result in the Wolf-Hirschhorn syndrome and can result in an apparently normal phenotype. We speculate that homology between subterminal repeat sequences on 4p and sequences on the acrocentric short arms may explain the origin of the rearrangement and that position effect may play a role in the expression of the abnormal phenotype.
我们报告了两个携带卫星染色体4短臂（4ps）的家族。卫星和随体通常出现在近端着丝粒染色体的短臂上；然而，文献中有几篇关于携带卫星的非近端着丝粒染色体的报道，推测这是由与近端着丝粒染色体的易位导致的。这是关于4ps染色体的首次报道。我们的家族很特别，因为未受影响和受影响的个体都携带4ps染色体。在受影响个体中观察到的表型虽然不同，但足以促使人们寻找4号染色体短臂的缺失。通过Southern印迹分析和荧光原位杂交，发现了从4p末端大约150 kb处的物质缺失。这个缺失很值得注意，因为它不会导致沃尔夫-赫希霍恩综合征，并且可能导致明显正常的表型。我们推测4p上的亚末端重复序列与近端着丝粒短臂上的序列之间的同源性可能解释了这种重排的起源，并且位置效应可能在异常表型的表达中起作用。
