Wen Yu, He Tianyi, Chen Min
Department of Pediatrics, Tongji Hospital Affiliated to Tongji Medical College, Huazhong University of Science and Technology, Wuhan, Hubei 430030, China.
Zhonghua Yi Xue Yi Chuan Xue Za Zhi. 2023 Nov 10;40(11):1420-1424. doi: 10.3760/cma.j.cn511374-20211030-00866.
To explore the clinical and genetic characteristics of a boy with isolated maternal uniparental disomy of chromosome 20 [UPD(20)mat].
A child who was admitted to the Tongji Hospital Affiliated to Tongji Medical College of Huazhong University of Science and Technology on April 8,2021. was selected as the study subject. Phenotypic and endocrinological findings of the child were retrospectively analyzed. Whole exome sequencing (WES) and methylation-specific multiplex ligation-dependent probe amplification (MS-MLPA) were carried out for detecting the UPD sequences and copy number variations. Both of his parents were verified by Sanger sequencing. Relevant literature was systematically reviewed.
The child, a 3-year-and-8-month-old boy born to a 41-year-old mother by Cesarean delivery at 36 gestational weeks due to oligohydramia, had a birth weight of 2 300 g and length of 46 cm. He was admitted to the NICU for feeding difficulties which had persisted despite of clinical management. At the age of 3.75, he had a height of 92.5 cm (< 3rd percentile; 25th ~ 50th percentile at 2.5 years) and a weight of 10.8 kg (< 3rd percentile; 50th percentile at 15 months). He had also presented with growth retardation, short stature, attention deficit and hyperactivity disorder (ADHD), mild mental retardation, and speech and language development disorders. He had simian creases in both hands but no additional dysmorphic signs, and his motor development was normal. Serum insulin, thyroid-stimulating hormone, and insulin growth factor binding protein 3 levels were within the normal ranges, though insulin growth factor-1 (IGF-1) was slightly decreased. Since that time he had continuously used atomoxetine hydrochloride capsules to control his ADHD. WES and MS-MLPA revealed the existence of UPD (20)mat.
The UPD(20)mat syndrome is characterized by feeding difficulties, growth retardation and short stature. The child in our case has been accompanied by ADHD and speech and language development disorders, which required long-term treatment. For women with advanced maternal age and suggestive phenotypes, genetic testing and counseling should be conducted.
探讨一名患有20号染色体单亲二体[UPD(20)mat]的男孩的临床和遗传特征。
选取2021年4月8日入住华中科技大学同济医学院附属同济医院的一名儿童作为研究对象。对该儿童的表型和内分泌学检查结果进行回顾性分析。采用全外显子组测序（WES）和甲基化特异性多重连接依赖探针扩增（MS-MLPA）检测UPD序列和拷贝数变异。通过桑格测序对其父母进行验证。系统回顾相关文献。
该儿童为3岁8个月男孩，其母亲41岁，因羊水过少于孕36周剖宫产分娩，出生体重2300g，身长46cm。因喂养困难入住新生儿重症监护病房，尽管经过临床处理，喂养困难仍持续存在。3.75岁时，他身高92.5cm（<第3百分位数；2.5岁时为第25~50百分位数），体重10.8kg（<第3百分位数；15个月时为第50百分位数）。他还存在生长发育迟缓、身材矮小、注意力缺陷多动障碍（ADHD）、轻度智力障碍以及言语和语言发育障碍。双手有猿线，但无其他畸形体征，运动发育正常。血清胰岛素、促甲状腺激素和胰岛素生长因子结合蛋白3水平在正常范围内，不过胰岛素生长因子-1（IGF-1）略有下降。自那时起，他持续使用盐酸托莫西汀胶囊控制ADHD症状。WES和MS-MLPA检测显示存在UPD(20)mat。
UPD(20)mat综合征的特征为喂养困难、生长发育迟缓和身材矮小。本病例中的儿童还伴有ADHD以及言语和语言发育障碍，需要长期治疗。对于高龄产妇且有提示性表型的女性，应进行基因检测和咨询。
