Valencia-Peña Claudia, Jiménez-Sanchez Paula, Saldarriaga Wilmar, Payán-Gómez César
Department of Ophthalmology, Faculty of Health, Universidad del Valle, Cali, Colombia.
Medical and surgery student, Universidad del Valle, Cali, Colombia.
BMC Ophthalmol. 2020 Aug 17;20(1):333. doi: 10.1186/s12886-020-01603-w.
22q11.2 duplication syndrome (Dup22q11.2) has reduced penetrance and variable expressivity. Those affected may have intellectual disabilities, dysmorphic facial features, and ocular alterations such as ptosis, hypertelorism, nystagmus, and chorioretinal coloboma. The prevalence of this syndrome is unknown, there are only approximately 100 cases reported. However Dup22q11.2 should have a similar prevalence of DiGeorge syndrome (1 in each 4000 new-borns), in which the same chromosomal region that is duplicated in Dup22q11.2 is deleted.
We report a patient with intellectual disability, psychomotor development delay, hearing loss with disyllable pronunciation only, hyperactivity, self-harm, hetero-aggressive behaviour, facial dysmorphism, left facial paralysis, post-axial polydactyly, and for the first time in patients with Dup22q11.2, optic nerve coloboma and dysplasia in optic nerve. Array comparative genomic hybridization showed a 22q11.23 duplication of 1.306 million base pairs.
New ocular findings in Dup22q11.2 syndrome, such as coloboma and dysplasia in the optic nerve, are reported here, contributing to the phenotypic characterization of a rarely diagnosed genetic syndrome. A complete characterization of the phenotype is necessary to increase the rate of clinical suspicion and then the genetic diagnostic. In addition, through bioinformatics analysis of the genes mapped to the 22q11.2 region, it is proposed that deregulation of the SPECC1L gene could be implicated in the development of ocular coloboma.
22q11.2重复综合征（Dup22q11.2）具有较低的外显率和可变的表现度。患者可能有智力残疾、面部畸形特征以及眼部改变，如眼睑下垂、眼距过宽、眼球震颤和脉络膜视网膜缺损。该综合征的患病率尚不清楚，仅报告了约100例病例。然而，Dup22q11.2的患病率应与DiGeorge综合征相似（每4000名新生儿中有1例），在DiGeorge综合征中，Dup22q11.2中重复的相同染色体区域发生缺失。
我们报告了一名患者，有智力残疾、精神运动发育迟缓、仅能发双音节的听力损失、多动、自伤行为、攻击他人行为、面部畸形、左侧面瘫、轴后多指畸形，并且在Dup22q11.2患者中首次发现视神经缺损和视神经发育异常。阵列比较基因组杂交显示22q11.23有130.6万个碱基对的重复。
本文报告了Dup22q11.2综合征新的眼部表现，如视神经缺损和发育异常，有助于对这种罕见诊断的遗传综合征进行表型特征描述。完整的表型特征描述对于提高临床怀疑率进而提高基因诊断率是必要的。此外，通过对定位到22q11.2区域的基因进行生物信息学分析，提出SPECC1L基因的失调可能与眼部缺损的发生有关。
