Uwineza A, Pierquin G, Gaillez S, Jamar M, Hellin A C, Caberg J H, Bours V
Center for Human Genetics, Centre Hospitalier Universitaire Sart-Tilman, University of Liège, Belgium.
Genet Couns. 2013;24(2):193-200.
The occurrence of mosaic ring chromosome 13 is rare. The mechanism of ring chromosome formation is usually associated with loss of genetic material. We report 2 cases of mosaic ring chromosome 13, resulting in deletion of 13qter. The first patient, a 15 year-old boy, presented a delayed psychomotor development, mental retardation, dysmorphic features and bleeding disorders associated with a de novo terminal 13q34 deletion. The second case was a foetus of 31 weeks with prenatal diagnosis of severe malformation such as holoprosencephaly, congenital cardiac defects, gastro-intestinal abnormalities with intrauterine growth retardation, the molecular analysis showed a de novo deletion encompassing the region 13q31.3-q34.
嵌合型13号环状染色体的发生较为罕见。环状染色体形成的机制通常与遗传物质的丢失有关。我们报告了2例嵌合型13号环状染色体病例，导致13qter缺失。首例患者为一名15岁男孩，表现为精神运动发育迟缓、智力障碍、畸形特征以及与新发13q34末端缺失相关的出血性疾病。第二例是一名31周的胎儿，产前诊断出严重畸形，如前脑无裂畸形、先天性心脏缺陷、胃肠道异常以及宫内生长迟缓，分子分析显示存在一个包含13q31.3 - q34区域的新发缺失。
