关键词: 超声软指标, 染色体微阵列, 核型分析

Abstract: Objective: To find the genetic etiology of fetuses with abnormal ultrasound soft index using chromosome karyotype analysis and chromosome microarray analysis technology and to evaluate its application value.Methods: From January 2018 to April 2020, 90 cases of ultrasound diagnosed fetuses with abnormal soft index were collected in the second trimester of amniotic fluid, chromosome karyotype analysis and chromosome microarray detection were performed, and ultrasonic soft index were analyzed genetically.Results: Ninety cases of abnormal fetal soft index were diagnosed by ultrasound. The detection rate of abnormal ultrasound soft index CNVs was 35.6% (32/90). Among them, benign accounted for 12.5% (4/32), the detection rate of VOUS was 56.2% (18/32), the detection rate of pathogenic CNV was 31.2% (10/32), and 10 cases were induced. There were 73 cases with only abnormal soft indicators and 17 cases with two or more soft indicators. There were 6 cases of pathogenic CNVs detected in two or more abnormal soft index cases, accounting for 35.3% (6/17), which was significantly higher than the detection rate of simple soft index abnormality 5.5%(4/73). The chromosome karyotype analysis showed no abnormalities. CMA detected two abnormal cases, accounting for 20% (2/10) of the pathogenic cases, avoiding the birth of two defective babies. Conclusion: The application of chromosome karyotype analysis combined with CMA detection can improve the genetic detection rate of fetuses with abnormal ultrasound soft index, and further prenatal diagnosis and genetic counseling should be carried out for fetuses with abnormal ultrasound soft index.

Key words: soft ultrasound index, chromosome microarray, karyotype analysis, fetuses