Application of chromosome microarray analysis for prenatal diagnosis of a fetus with partial duplication of 1p and uniparental disomy of chromosome 6 / 中华医学遗传学杂志

ABSTRACT

<p><b>OBJECTIVE</b>To explore the genetic cause for a fetus with structural anomaly, and to correlate the phenotype with the genotype.</p><p><b>METHODS</b>Amniotic fluid was obtained following the revelation of structural anomaly by ultrasonography. Cell culture and direct DNA extraction were performed in parallel. G-banded karyotyping analysis and chromosome microarray analysis (CMA) were subsequently carried out.</p><p><b>RESULTS</b>G-banded karyotyping has suggested the fetus to be a normal male. However, CMA analysis has revealed the presence of a mosaic 3.24 Mb duplication of 1p36.33p36.32 (24%) and uniparental disomy (UPD) of chromosome 6. The genetic diagnosis for the fetus was therefore 46,XY, arr 1p36.33 p36.32(849,466-4,090,472)×2-3, (6)×2 hmz. The anomaly can probably explain the ultrasound findings in the fetus.</p><p><b>CONCLUSION</b>Compared with conventional cytogenetic methods, CMA has greater resolution and throughput, and can serve as a more efficient platform for the detection of chromosomal microdeletion, microduplication, loss of heterozygosity and UPD.</p>