Objective: To analysis the incidence of abnormal genetics and the clinical outcome of fetuses with ultrasonic nonstructural abnormality. Methods: This study was conducted retrospectively. 631 pregnant women were enrolled in the Prenatal Diagnostic Center of Fujian Maternal and Child Health Hospital due to ultrasonic nonstructural abnormality from January 2016 to January 2019. According to different gestational weeks, amniotic fluid or umbilical cord blood samples were collected for chromosome karyotype analysis and SNP-array. According to the number of nostructural abnormalities, they were divided into 1 nostructural abnormality group, 2 nostructural abnormalities group, and ≥3 nostructural abnormalities group. Chi-square test was used for comparison between groups. Results: Of the 631 cases, 34 cases (5.4%, 34/631) had abnormal karyotypes, including 20 cases with abnormal chromosome number and 14 cases with abnormal chromosome structure. In results of SNP-array, there were 53 abnormal results (8.4%, 53/631), including 32 cases of pathogenic copy number variations (CNV) and 21 cases of variations of uncertain clinical significance (VOUS). The rates of pathogenic CNV were 4.57% (21/260), 4.76% (7/147) and 16.67% (4/24) in the group of 1, 2 and ≥3 nostructural abnormalities, respectively. The rate of the three groups showed a linear trend, and the difference was statistically significant (χ²=7.419,P<0.05). In the single nostructural abnormality group, the rate of pathogenic CNV of nasal bone dysplasia, fetal growth restriction (FGR) and thickened nuchal translucency (NT) were 8.11% (3/37), 7.04% (5/71) and 5.60% (7/125), respectively. Conclusions: Compared with the karyotype analysis, SNP-array can significantly improve the detection rate of genetic abnormalities in ultrasonic nonstructural abnormality. When multiple ultrasonic nonstructural abnormality were combined, the risk of genetic abnormalities showed an upward trend.
目的： 分析超声非结构异常胎儿的基因组异常发生率，及其对妊娠结局的影响。 方法： 采用回顾性研究，收集2016年1月至2019年1月在福建省妇幼保健院产前诊断中心因超声非结构异常而进行介入性产前诊断的631例孕妇。根据孕周不同抽取羊水标本或脐带血标本进行染色体核型分析及单核苷酸多态性微阵列分析（SNP-array）。按超声非结构异常指标数目分为1个超声非结构异常组、2个超声非结构异常组、≥3个超声非结构异常组，组间比较采用卡方检验。 结果： 染色体核型分析发现异常核型34例（5.39%，34/631），其中染色体数目异常20例，染色体结构异常14例。SNP-array检测发现异常结果53例（8.40%，53/631），包括致病性拷贝数变异（CNV）32例及不明意义变异（VOUS）21例。1个超声非结构异常组、2个超声非结构异常组、≥3个超声非结构异常组致病性CNV 检出率分别为4.57%（21/260）、4.76%（7/147）、16.67%（4/24），其检出率的差异有统计学意义（χ²=7.419，P<0.05）。单一非结构异常组中，鼻骨发育不良、胎儿生长发育受限（FGR）、颈部透明层厚度增厚（NT）的致病性CNV检出率相对较高，分别为 8.11%（3/37）、7.04%（5/71）、5.60%（7/125）。 结论： SNP-array技术相对传统的染色体核型分析，可能显著提高超声非结构异常胎儿遗传学异常的检出。合并多个超声非结构异常时，染色体异常的风险呈上升趋势。.