Hunter Matthew, Bruno Damien, Amor David J
Royal Children's Hospital, Melbourne, Australia.
Am J Med Genet A. 2009 Aug;149A(8):1763-7. doi: 10.1002/ajmg.a.32954.
Extra structurally abnormal chromosomes (ESACs) derived from the X chromosome are rare. We report a non-mosaic ESAC derived from the X chromosome in a 3-year-old female who presented with early hypotonia, developmental delay, hypertelorism, low set ears, and small hands and feet. The breakpoints of the ESAC were mapped by SNP microarray to Xp11.1-p11.22, a region encompassing 7.17 Mb and containing 110 known or putative genes and excluding the X-inactivation center. A review of other reported patients with karyotypes that cause functional disomy of proximal Xp allows delineation of a common phenotype comprising early hypotonia, cognitive impairment, hypertelorism, myopia, small hands and feet and abnormal external ears.
源自X染色体的结构异常额外染色体（ESACs）很罕见。我们报告了一名3岁女性患者，其存在一条源自X染色体的非嵌合ESAC，该患者表现为早期肌张力减退、发育迟缓、眼距增宽、低位耳以及小手和小脚。通过单核苷酸多态性（SNP）微阵列将该ESAC的断点定位到Xp11.1-p11.22，该区域跨度为7.17 Mb，包含110个已知或推测的基因，且不包括X染色体失活中心。对其他报道的具有导致近端Xp功能二体化核型的患者进行回顾，可勾勒出一种常见表型，包括早期肌张力减退、认知障碍、眼距增宽、近视、小手和小脚以及外耳异常。
