Mosaic Variegated Aneuploidy Syndrome (MVA) is a rare autosomal recessive disorder characterized by mosaic aneuploidies involving multiple chromosomes and tissues. Affected individuals typically present with severe intrauterine and postnatal growth retardation, microcephaly, facial dysmorphism, developmental delay and predisposition to cancer and epilepsy. Three genes, BUB1B, CEP57 and TRIP13, are involved in this syndrome. Only 7 patients carrying pathogenic variants in CEP57 are reported to date. Here we report two adult brothers born to Moroccan related parents, who presented with intrauterine and postnatal growth retardation, microcephaly, facial dysmorphism, learning disabilities, skeletal anomalies with thumb hypoplasia and dental abnormalities. Both brothers have mosaic variegated aneuploidies on blood karyotype. A previously reported homozygous 11 bp duplication was identified in CEP57 in the two brothers. We propose that a FoSTeS (Fork Stalling and Template Switching) mechanism could be involved in the occurrence of this duplication. This report expands the phenotypical spectrum associated with CEP57 and highlights the interest of blood karyotype in patients presenting with short stature and microcephaly.

马赛克杂色非整倍体综合症（MVA）是一种罕见的常染色体隐性遗传病，其特征是涉及多个染色体和组织的马赛克非整倍性。受影响的个体通常表现为严重的子宫内和产后生长迟缓，小头畸形，面部畸形，发育延迟以及易患癌症和癫痫病。该综合征涉及三个基因BUB1B，CEP57和TRIP13。仅7例携带CEP57致病变异的患者至今为止。在这里，我们报告了两个摩洛哥亲生父母的成年兄弟，他们表现出宫内和产后发育迟缓，小头畸形，面部畸形，学习障碍，骨骼发育异常，拇指发育不全和牙齿异常。兄弟俩在血核型上都有镶嵌杂色的非整倍性。在两个兄弟的CEP57中鉴定出先前报道的纯合11 bp复制。我们建议，FoSTeS（货叉停顿和模板切换）机制可以参与此重复的发生。该报告扩展了与CEP57相关的表型谱，并强调了身材矮小和小头畸形患者对血型核型的兴趣。