Background: Here we describe a new case of partial distal 10q trisomy in a 6-year-old Iranian girl from healthy parents with mental, growth, and psychomotor retardations.

Methods: Additional clinical features include dysmorphic craniofacial features, microcephaly, bilateral hydronephrosis without heart problems, small and rotated low-set ears, bow-shaped mouth, abnormal teeth, short neck, and as a first case reported, fingers with camptodactly (i.e., without any furrows or ridges in the palms and fingers).

Results: Cytogenetic analysis (GTG-banding) revealed an unbalanced female karyotype with additional bands at the end of the long arm of chromosome 10, karyotype: 46,XX,dup(10)(q25q26). Conclusion: According to the banding pattern it is most likely that a duplication of the distal part of the long arm of chromosome 10 occurred.