■15q11.2微缺失可导致影响神经系统的综合征。然而,15q11.2微缺失具有较大的表型差异和不完全的外显率，这给产前诊断带来了挑战。我们报告了华东地区21例15q11.2微缺失胎儿，并复习了与缺失变异相关的产前临床特征的文献，为产前遗传咨询提供依据。
■回顾性分析2018年6月至2021年9月收集的21例15q11.2微缺失胎儿的临床资料，和染色体微阵列分析。对报道的15q11.2微缺失胎儿的产前临床特征进行了回顾和总结。对20项研究进行了荟萃分析，以测试异质性，数据集成，15q11.2微缺失与神经精神疾病相关性的敏感性。
■女性的中位年龄为29.5岁。介入检查的中位孕龄为24周。所有胎儿都显示出15q11.2片段的缺失变体，中位缺失范围约为0.48MB。5例超声检查未见异常，但其中4例显示唐氏综合征的高风险(风险值分别为1/184,1/128,1/47和1/54).其余16例胎儿均表现为先天性心脏病(7/16),颈部半透明度升高（5/16），大脑结构异常（2/16）和肾脏疾病（2/16）。在82例产前病例的文献综述中，44％（36/82）有异常的超声特征，31%(11/36)的颈部透明异常，约28%（10/36）显示心脏结构异常，14％（5/36）有脑结构异常。荟萃分析显示，精神分裂症和癫痫患者15q11.2微缺失突变频率明显高于正常人（比值比2.04，95％置信区间：1.78-2.33，p<0.00001；比值比5.23，95％置信区间：2.83-9.67，p<0.00001）。
■超过一半的15q11.2微缺失病例在产前超声检查中没有出现异常。有超声特征的病例主要表现为孤立性畸形，如颈项半透明度升高，先天性心脏病,大脑结构异常.产后15q11.2微缺失患者患精神分裂症的风险增加，癫痫,和其他神经和精神疾病从15q11.2微缺失。因此,15q11.2微缺失的产前诊断不仅依赖于分子诊断技术，还需要谨慎的遗传咨询。
UNASSIGNED: 15q11.2 microdeletion can lead to syndromes affecting the nervous system. However, 15q11.2 microdeletion has large phenotypic differences and incomplete penetrance, which brings challenges to prenatal diagnosis. We reported 21 cases of 15q11.2 microdeletion fetuses in Eastern
China and reviewed literature on the prenatal clinical characteristics related to the deletion variants to provide a basis for prenatal genetic counseling.
UNASSIGNED: The clinical data of 21 cases of 15q11.2 microdeletion fetuses collected from June 2018 to September 2021 were retrospectively analyzed, and chromosomal microarray analysis was performed. The reported prenatal clinical features of 15q11.2 microdeletion fetuses were reviewed and summarized. A meta-analysis of 20 studies was performed to test heterogeneity, data integration, and sensitivity on the correlation between 15q11.2 microdeletion and neuropsychiatric diseases.
UNASSIGNED: The median age of the women was 29.5 years. The median gestational age at interventional examination was 24 weeks. All fetuses showed deletion variants of the 15q11.2 fragment, and the median deletion range was approximately 0.48 MB. Ultrasound of five cases showed no abnormalities; however, four of them showed a high risk of Down\'s syndrome (risk values were 1/184, 1/128, 1/47, and 1/54, respectively). The remaining 16 fetuses showed congenital heart disease (7/16), elevated nuchal translucency (5/16), abnormal brain structure (2/16) and renal disease (2/16). In a literature review of 82 prenatal cases, 44% (36/82) had abnormal ultrasound features, 31% (11/36) showed abnormal nuchal translucency, approximately 28% (10/36) showed abnormal cardiac structure, and 14% (5/36) had brain structural abnormalities. The meta-analysis revealed that the frequency of the 15q11.2 microdeletion mutation in patients with schizophrenia and epilepsy was significantly higher (odds ratio 2.04, 95% confidence interval: 1.78-2.33, p < 0.00001; odds ratio 5.23, 95% confidence interval: 2.83-9.67, p < 0.00001) than that in normal individuals.
UNASSIGNED: More than half of the 15q11.2 microdeletion cases presented no abnormalities in prenatal ultrasound examination. The cases with ultrasound features mainly showed isolated malformations such as elevated nuchal translucency, congenital heart disease, and brain structural abnormalities. Postpartum 15q11.2 microdeletion patients are at an increased risk of suffering from schizophrenia, epilepsy, and other neurological and mental diseases from 15q11.2 microdeletion. Therefore, prenatal diagnosis of 15q11.2 microdeletion not only depends on molecular diagnostic techniques but also requires cautious genetic counseling.
