At the 43rd annual meeting of the ASHG in 1993, the senior author reported monozygotic twins with discordant phenotype due to a ring 13 chromosomal mosaic syndrome in one of them. Her major manifestations included: intrauterine growth restriction (IUGR), failure to thrive (FTT), delayed developmental milestones/intellectual disability (DDM/ID), left hemihypoplasia of her body with leg length discrepancy, left profound deafness due to inner ear malformation, telecanthus, dental anomalies mainly on the left side, congenital torticollis due to Klippel‐Feil anomaly, 13 ribs, scoliosis, dislocation of the left hip, and distinctive left hand and feet. A blood karyotype at age 3^1/2 was normal. Silver‐Russell syndrome was initially suspected; however, at age 4, a karyotype on skin fibroblasts showed a ring 13 chromosomal mosaicism, 46,XX,15s+/46,XX,‐13,+r(13),15s+, with a higher frequency on the left side of the body. Since then, we have been involved in the management of this patient for 30 years. This has ultimately allowed us to compare her achievements with her normal monozygotic twin. In this long term follow‐up, we want to emphasize the importance of: (a) early recognition of genetic syndromes, especially of mosaicisms, and of early intervention programs, (b) the involvement of different specialists in the management of patients with MCA, and (c) mentioning how familial and socioeconomic issues may limit or enhance the full potential of patients with some genetic disorders.

中文翻译：

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由于其中一个环 13 染色体嵌合而导致表型不一致的同卵双胞胎 30 年随访的经验教训

在 1993 年第 43 届 ASHG 年会上，资深作者报告了由于其中一个环 13 染色体镶嵌综合征导致表型不一致的单卵双胞胎。她的主要表现包括：宫内发育迟缓（IUGR）、发育迟缓（FTT）、发育里程碑/智力障碍（DDM/ID）延迟、身体左侧偏侧发育不良伴腿长差异、内耳畸形导致严重耳聋、 Telecanthus，主要在左侧的牙齿异常，由于 Klippel-Feil 异常导致的先天性斜颈，13 根肋骨，脊柱侧弯，左髋脱位，以及独特的左手和脚。3 ^1/2岁时的血核型很正常。最初怀疑 Silver-Russell 综合征；然而，在 4 岁时，皮肤成纤维细胞的核型显示出环状 13 染色体嵌合，46,XX,15s+/46,XX,‐13,+r(13),15s+，在身体左侧的频率更高. 从那时起，我们参与了该患者的管理已有 30 年。这最终使我们能够将她的成就与她正常的单卵双胞胎进行比较。在这项长期随访中，我们要强调以下方面的重要性：(a) 早期识别遗传综合征，尤其是嵌合体，以及早期干预计划，(b) 不同专家参与 MCA 患者的管理，以及 (c) 提及家庭和社会经济问题如何限制或增强某些遗传疾病患者的全部潜力。