[Diagnosis of a fetus with partial 17p trisomy using chromosomal microarray analysis]

Area of Science:

• Genetics
• Fetal Medicine
• Genomic Analysis

Background:

• Prenatal diagnosis of fetal malformations often involves chromosomal analysis.
• Identifying the genetic basis of complex fetal abnormalities requires advanced molecular techniques.

Observation:

• A fetus presenting with multiple malformations underwent SNP array and G banding chromosomal analysis.
• The fetus's father carried a balanced translocation, while the mother had a normal karyotype.

Findings:

• SNP array identified a significant 16 Mb duplication in the 17q24.2-q25.3 region of the fetus.
• The fetus's karyotype revealed a derivative chromosome 21 with a translocation involving chromosomes 17 and 21.

Implications:

• The identified copy number variation (CNV) at 17q24.2-q25.3 is strongly associated with the fetal malformations.
• SNP array analysis is crucial for detecting submicroscopic CNVs in fetuses with apparently balanced translocations.
• This technology complements traditional karyotyping, offering a more comprehensive genetic evaluation in prenatal diagnostics.