Prenatal diagnosis study using array comparative genomic hybridization for genotype-phenotype correlation in 772...

Area of Science:

• Prenatal Genetics
• Genomic Medicine
• Reproductive Health

Background:

• Prenatal diagnosis is crucial for identifying fetal genetic abnormalities.
• Copy number variations (CNVs) are significant contributors to congenital anomalies.
• Microarray-based comparative genomic hybridization (aCGH) offers high resolution for detecting CNVs.

Purpose of the Study:

• To evaluate indications for prenatal diagnosis.
• To determine the prevalence of pathogenic CNVs and variants of unknown significance (VUS).
• To highlight the clinical utility of aCGH in prenatal genetic testing.

Main Methods:

• Retrospective analysis of 772 fetuses undergoing genetic study over 9 years.
• Utilized aCGH for genetic analysis in two tertiary hospitals.
• Correlated genetic findings with clinical presentations.

Main Results:

• Detected pathogenic CNVs in 8.3% of fetuses, primarily associated with structural malformations (CNS, skeletal, cardiac).
• Increased nuchal translucency was a significant indication for detecting pathogenic CNVs.
• Found no significant difference in pathogenic CNV rates between structural and non-structural malformations, underscoring aCGH's value in diverse cases.
• Identified 217 cases with CNVs classified as VUS, predominantly involving chromosomes X, 1, and 16.

Conclusions:

• aCGH demonstrated a 4.9% increase in diagnostic yield over conventional karyotyping.
• aCGH enhances the accuracy and diagnostic power of prenatal testing.
• Genotype-phenotype correlation from aCGH aids in variant classification and genetic counseling.