Abstract：
OBJECTIVE: We aimed to identify the genetic cause of one hydrops fetalis with Noonan syndrome (NS) manifestations including increased nuchal translucency (INT) and ascites through prenatal whole exome sequencing (WES).
METHODS: The case is a gestational age (GA) 18 fetus of two healthy parents with a normal child. We proceeded the genomic DNA from both fetus amniotic cells and parents to WES and identified a RIT1 mutation (c.268A>G) as the pathogenic cause of the hydrops fetalis by automatic prioritization algorithm after array-comparative genomic hybridization results showing negative.
CONCLUSIONS: Mutations in RIT1 have been reported as the causes for different fetus structural abnormities in the recent years. This case contributes to the summary delineations of the prenatal NS phenotypes related to RIT1 mutation. In addition, the fast WES application, in this case, has demonstrated its advantage in prenatal disorder diagnosis when conventional karyotyping or chromosomal microarray testing result is negative.
METHODS: The case is a gestational age (GA) 18 fetus of two healthy parents with a normal child. We proceeded the genomic DNA from both fetus amniotic cells and parents to WES and identified a RIT1 mutation (c.268A>G) as the pathogenic cause of the hydrops fetalis by automatic prioritization algorithm after array-comparative genomic hybridization results showing negative.
CONCLUSIONS: Mutations in RIT1 have been reported as the causes for different fetus structural abnormities in the recent years. This case contributes to the summary delineations of the prenatal NS phenotypes related to RIT1 mutation. In addition, the fast WES application, in this case, has demonstrated its advantage in prenatal disorder diagnosis when conventional karyotyping or chromosomal microarray testing result is negative.
摘要：
目的：我们旨在通过产前全外显子组测序（WES）确定一种胎儿水肿伴努南综合征（NS）表现的遗传原因，包括颈部透明层（INT）和腹水增加。
方法：该病例是两个健康父母和一个正常孩子的胎龄（GA）18胎儿。我们将来自胎儿羊膜细胞和父母的基因组DNA进行到WES，并在阵列-比较基因组杂交结果显示阴性后，通过自动优先排序算法确定RIT1突变（c.268A>G）为胎儿水肿的致病原因。
结论：近年来已报道RIT1突变是不同胎儿结构异常的原因。此病例有助于总结与RIT1突变相关的产前NS表型。此外,快速WES应用程序，在这种情况下,当常规核型分析或染色体微阵列检测结果为阴性时，已证明其在产前疾病诊断中的优势。
方法：该病例是两个健康父母和一个正常孩子的胎龄（GA）18胎儿。我们将来自胎儿羊膜细胞和父母的基因组DNA进行到WES，并在阵列-比较基因组杂交结果显示阴性后，通过自动优先排序算法确定RIT1突变（c.268A>G）为胎儿水肿的致病原因。
结论：近年来已报道RIT1突变是不同胎儿结构异常的原因。此病例有助于总结与RIT1突变相关的产前NS表型。此外,快速WES应用程序，在这种情况下,当常规核型分析或染色体微阵列检测结果为阴性时，已证明其在产前疾病诊断中的优势。
