Macayran Joanne F, Cederbaum Stephen D, Fox Michelle A
Department of Pediatrics, David Geffen School of Medicine, University of California, Los Angeles, California.
Am J Med Genet A. 2006 Nov 1;140(21):2320-3. doi: 10.1002/ajmg.a.31459.
There is a standard recommendation that chromosomes be obtained in any patient who presents with developmental delay (DD) or mental retardation (MR) regardless of whether or not they have dysmorphic features. Increasingly, if patients are physically well-formed, the option to perform a karyotype is questioned because of the presumed low yield of a chromosomal abnormality. We hypothesize that patients with DD/MR who are non-dysmorphic do not have abnormal chromosomes at a rate high enough to warrant obtaining a karyotype on all patients in this population. A retrospective analysis of patients with DD/MR who were non-dysmorphic was performed. The total number of subjects was 134. Of these, 120 patients were recommended to have high-resolution chromosomes performed, among whom seven were lost to follow-up. In the remaining 113 patients, all had normal karyotypes. Three subjects were found to have fragile X syndrome, accounting for 3% of the males. One subject had a pathological mutation in MECP2. Our yield of chromosome analysis in non-dysmorphic patients with DD/MR is less than that previously described. The role of array-comparative genomic hybridization (array-CGH) as an auxiliary or alternative procedure in this patient population will be discussed.
有一项标准建议，即对于任何出现发育迟缓（DD）或智力障碍（MR）的患者，无论其是否有畸形特征，都应进行染色体检查。越来越多的情况是，如果患者身体形态正常，由于推测染色体异常的检出率较低，进行核型分析的选择就会受到质疑。我们假设，非畸形的DD/MR患者染色体异常的发生率不足以高到保证对该人群的所有患者都进行核型分析。对非畸形的DD/MR患者进行了回顾性分析。受试者总数为134人。其中，120例患者被建议进行高分辨率染色体检查，其中7例失访。在其余113例患者中，所有患者的核型均正常。3名受试者被发现患有脆性X综合征，占男性的3%。1名受试者的MECP2基因发生了病理性突变。我们对非畸形的DD/MR患者进行染色体分析的检出率低于先前描述的水平。将讨论阵列比较基因组杂交（array-CGH）作为该患者群体辅助或替代检查方法的作用。
