Background: During conventional karyotyping, it can be difficult to clearly identify de novo interstitial deletion of a chromosomal band when there are similar bands nearby.
Case: A 38-year-old, pregnant woman underwent genetic amniocentesis at 18 weeks of gestation due to advanced maternal age. Chromosomal studies detected an interstitial deletion at the long arm of 1 chromosome 2. Array-based comparative genomic hybridization further located the deletion in the band of interstitial 2q14.2-2q21.3. Prenatal ultrasound revealed borderline ventriculomegaly without additional abnormalities of the cardiovascular, urinary or gastrointestinal systems or the spine. Fetal magnetic resonance imaging identified mild dilatation of the posterior horns of the lateral ventricles. At 5 months after birth, the infant had febrile convulsions that were well controlled with medication. A single incisor was noted at 1 year of age. Atrophy of the left, undescended testis and developmental delay were also noted.
Conclusion: Array-based comparative genomic hybridization is helpful in prenatal diagnosis because it can precisely locate the chromosome bands with copy number changes. Clinical manifestations in this case provide valuable information for genetic counseling pregnant women who conceive a fetus with deletion of interstitial 2q14.2-2q21.3.