[Analysis of genomic copy number variations in fetuses with conotruncal defects using single nucleotide polymorphism...

Area of Science:

• Medical Genetics
• Fetal Medicine
• Echocardiography

Background:

• Conotruncal defects (CTD) are a significant group of congenital heart defects.
• Echocardiography is crucial for prenatal detection of fetal CTD.
• Standard karyotyping may not identify the genetic cause in all fetuses with CTD.

Purpose of the Study:

• To evaluate the diagnostic utility of single nucleotide polymorphism (SNP) array in fetuses with echocardiographically detected CTD.
• To determine the rate of pathogenic copy number variations (CNVs) in fetuses with CTD and normal karyotypes.

Main Methods:

• SNP array analysis was performed on 75 fetuses diagnosed with CTD via ultrasound and having a normal karyotype.
• ChAS software was utilized for the analysis of SNP array data.
• Detection and classification of copy number variations (CNVs) were performed.

Main Results:

• Pathogenic CNVs were identified in 9.3% (7/75) of the fetuses.
• Variants of uncertain significance (VOUS) were found in 2.7% (2/75) of cases.
• Benign CNVs were detected in 25.3% (19/75) of the study cohort.

Conclusions:

• SNP array is a valuable tool for determining the genetic etiology of fetal CTD.
• This method is particularly effective for investigating fetuses with CTD who have a normal karyotype.
• SNP array analysis can reveal underlying genetic causes missed by conventional karyotyping.