Phenotypic overlapping of trisomy 12p and Pallister-Killian syndrome.

Trisomy of 12p is a rare chromosomal abnormality, which sometimes coexists with other chromosomal anomalies. We report on a patient with a supernumerary chromosome involving chromosomes 12 and 14, which was confirmed by array-comparative genomic hybridization (aCGH). He had developmental delay and dysmorphic features overlapped with those of Pallister-Killian syndrome, which is derived from an isodicentric chromosome 12. The microblepharon identified in our patient is a characteristic feature of 12p trisomy. Further patients are needed to establish the phenotypic difference between trisomy 12p and Pallister-Killian syndrome.