Murru D, Boccone L, Ristaldi M S, Nucaro A L
Dipartimento di Scienze Biomediche e Biotecnologie, Università di Cagliari, Italy.
Genet Couns. 2008;19(4):381-6.
The Cri du Chat Syndrome (CdCS) is one of the most common deletion syndromes, involving the short arm of chromosome 5, with an incidence of 1 in 50.000 live births. The following are the characteristic features of this syndrome: microcephaly, hypertelorism, round face, micrognatia, epicanthic folds, prominent nasal bridge, hypotonia and severe psychomotor retardation. Patients also show a high pitched cry similar to the mewing of a cat. Deletions and duplications of chromosome 5p have been described in the literature. Mosaicism represents only 3% of this cytogenetic aberration. Up to date, only cases of de novo 5p mosaic anomalies involving two or three rearranged cell lines, with deletions and duplications, have been described. Herein, we report the first case of a patient affected by multiple congenital anomalies and a mosaicism, with two rearranged cell lines: one with a 5p deletion; the other with a 5p deletion/duplication. Our patient did not show the characteristic features described in patients with 5p duplications, but a phenotype compatible with the CdCS. Our case represents the first description of a mosaicism with deletion and deletion/duplication of a portion of the short arm of chromosome 5.
猫叫综合征（CdCS）是最常见的缺失综合征之一，涉及5号染色体短臂，活产发病率为1/50000。该综合征的特征如下：小头畸形、眼距过宽、圆脸、小颌畸形、内眦赘皮、鼻梁突出、肌张力减退和严重精神运动发育迟缓。患者还会发出类似猫叫的高音调哭声。文献中已描述了5号染色体短臂的缺失和重复。嵌合体仅占这种细胞遗传学异常的3%。迄今为止，仅描述了涉及两到三个重排细胞系、伴有缺失和重复的新发5号染色体短臂嵌合异常病例。在此，我们报告首例患有多种先天性异常和嵌合体的患者，其有两个重排细胞系：一个带有5号染色体短臂缺失；另一个带有5号染色体短臂缺失/重复。我们的患者未表现出5号染色体短臂重复患者所描述的特征性表现，而是具有与猫叫综合征相符的表型。我们的病例是首例关于5号染色体短臂部分缺失和缺失/重复嵌合体的描述。
