Trisomy 16q21 right arrow qter: Seven-year follow-up of a girl with unusually long survival

The 16q21 right arrow qter duplication is a chromosomal abnormality rarely found in liveborn infants, with only four published cases. We report here on the 7-year follow-up of a female patient with trisomy 16q21 right arrow qter due to a maternal balanced translocation t(4; 16)(q35.2; q21). The patient shows severe mental retardation, congenital heart malformations, nephropathy, and other congenital anomalies. The derivative chromosome was characterized by GTG banding, fluorescent in situ hybridization (FISH) with different BAC probes and the array technique, in order to map the breakpoints. The patient has a 16q21 right arrow qter duplication, with a 4q35 right arrow qter monosomy, which we assume does not contribute to the abnormal phenotype. This is the first reported case of postnatal survival to the age of 7 years, an unusually long time in this chromosomal syndrome. 2010 Wiley-Liss, Inc.