HUSLAB Department of Clinical Genetics, Helsinki University Hospital, Department of Medical and Clinical Genetics, University of Helsinki, Helsinki, Finland.
Department of Obstetrics and Gynecology, Fetomaternal Medical Center, Helsinki University Hospital and University of Helsinki, Helsinki, Finland.
Prenat Diagn. 2021 Mar;41(4):422-433. doi: 10.1002/pd.5877. Epub 2020 Dec 31.
To find out whether the diagnostic yield of prenatal array comparative genomic hybridization (aCGH) can be improved by targeting preselected high-risk pregnancies.
All the in-house arrays ordered by the Fetomaternal Medical Center from February 2016 until December 2018 were retrospectively analyzed. The indications for array analysis included fetal structural abnormalities, increased nuchal translucency ≥3.5 mm and a chromosomal abnormality in a parent or a sibling. Common aneuploidies were excluded.
Diagnostic yield was 15.1% in the entire patient cohort and as high as 20% in fetuses with multiple structural anomalies. The diagnostic yield was lowest in the group with isolated growth retardation. A total of 76 copy number variants (CNVs) were reported from a total of 65 samples, including 16 CNVs associated with a well-described microdeletion/microduplication syndrome, six autosomal trisomies in mosaic form, and three pathogenic single-gene deletions with dominant inheritance and 12 CNVs known to be risk factors for eg developmental delay.
The diagnostic yield of aCGH was higher than what has previously been reported in less defined patient cohorts. However, the number of CNVs with unclear correlation to the fetal ultrasound findings was still relatively high. The importance of adequate pre- and posttest counseling must therefore be emphasized.
探讨针对选定的高危妊娠，产前 array 比较基因组杂交（aCGH）的诊断收益是否可以提高。
回顾性分析 2016 年 2 月至 2018 年 12 月期间 Fetomaternal Medical Center 内部订购的所有 array。array 分析的指征包括胎儿结构异常、颈项透明层（NT）增厚≥3.5mm 以及父母或兄弟姐妹的染色体异常。排除常见的非整倍体。
在整个患者队列中，诊断收益为 15.1%，在伴有多种结构异常的胎儿中高达 20%。在孤立性生长迟缓组中诊断收益最低。总共从 65 个样本中报告了 76 个拷贝数变异（CNV），包括 16 个与描述明确的微缺失/微重复综合征相关的 CNV、6 个嵌合形式的常染色体三体、3 个具有显性遗传的致病性单基因缺失和 12 个已知是发育迟缓等风险因素的 CNV。
aCGH 的诊断收益高于以前在定义不明确的患者队列中报道的水平。然而，与胎儿超声发现相关性不明确的 CNV 数量仍然相对较高。因此，必须强调充分的产前和产后咨询的重要性。
