Williams-Beuren综合征(WBS)是由7q11.23区域1.55-1.84Mb的半合子连续基因微缺失引起的。大约,28个基因已被证明有助于SWB的经典表型,存在畸形面部特征,主动脉瓣上狭窄(SVAS),智力残疾,和过度友好。随着基于微阵列的比较基因组杂交和其他分子细胞遗传学技术的使用,可以更准确地定义部分或非典型缺失,并完善基因型-表型相关性。这里,我们报道了一个罕见的基因组结构重排在7q11.23和XYY综合征与特征性临床体征的非典型缺失的男孩,但不足以诊断WBS。G显带的细胞遗传学分析显示核型47,XYY。使用试剂盒用MLPA(多重连接依赖性探针扩增)技术分析DNA,试剂盒组合(P064、P036、P070和P029)鉴定了7q11.23上的非典型缺失。此外,高分辨率SNP寡核苷酸微阵列分析(SNP-array)证实了MLPA发现的改变,并揭示了其他致病性CNV,在7号和X号染色体中。本报告显示了文献中尚未描述的关联,威廉姆斯-贝伦综合征和47,XYY之间。7q11.23中非典型缺失的鉴定伴随着其他基因组区域中的其他致病性CNV,可以更好地理解非典型基因组重排的临床后果。
Williams-Beuren syndrome (WBS) is caused by a hemizygous contiguous gene microdeletion of 1.55-1.84 Mb at
7q11.23 region. Approximately, 28 genes have been shown to contribute to classical phenotype of SWB with presence of dysmorphic facial features, supravalvular aortic stenosis (SVAS), intellectual disability, and overfriendliness. With the use of Microarray-based comparative genomic hybridization and other molecular cytogenetic techniques, is possible define with more accuracy partial or atypical deletion and refine the genotype-phenotype correlation. Here, we report on a rare genomic structural rearrangement in a boy with atypical deletion in
7q11.23 and XYY syndrome with characteristic clinical signs, but not sufficient for the diagnosis of WBS. Cytogenetic analysis of G-banding showed a karyotype 47,XYY. Analysis of DNA with the technique of MLPA (Multiplex Ligation-dependent Probe Amplification) using kits a combination of kits (P064, P036, P070, and P029) identified an atypical deletion on
7q11.23. In addition, high resolution SNP Oligonucleotide Microarray Analysis (SNP-array) confirmed the alterations found by MLPA and revealed others pathogenic CNVs, in the chromosomes 7 and X. The present report demonstrates an association not yet described in literature, between Williams-Beuren syndrome and 47,XYY. The identification of atypical deletion in
7q11.23 concomitant to additional pathogenic CNVs in others genomic regions allows a better comprehension of clinical consequences of atypical genomic rearrangements.