Partial trisomy of distal 19q detected by quantitative real‐time PCR and FISH in a girl with mild facial dysmorphism, hypotonia and developmental delay

We report on a 2 -year-old girl who was referred to us because of psychomotor developmental delay. She is the second child of healthy, non-consanguineous parents. Pregnancy and birth were uneventful. Milestones of motor development were delayed: grasping at 6 months, sitting without support at 16 months, crawling at 16 months and walking at 2 years of age. She spoke about five words and followed simple instructions. Banding cytogenetics revealed a numerically and structurally normal female karyotype of 46,XX. By quantitative real-time PCR analysis of all subtelomeric regions, a partial trisomy of the subtelomeric region of 19q could be detected. This result was confirmed by FISH-analysis with a subtelomeric probe for 19q. The additional material of chromosome 19q was localized on chromosome 6q. However, a deletion of the subtelomeric region of 6q could not be detected with a subtelomeric FISH probe for 6q. Conventional cytogenetic analysis as well as FISH with subtelomeric probes for 19q and 6q showed normal results in the parents. The detected chromosomal aberration probably occurred de novo. The clinical features are very likely to be caused solely by the partial trisomy 19q. © 2007 Wiley-Liss, Inc.