Partial mosaic trisomy 5: a new case report with ocular involvement.

We describe a new case of a male patient with a small marker chromosome present as 80% mosaic, derived from chromosome 5 with presence of posterior iridolenticular synechia, high hyperopia, epicanthic folds, hypertelorism, moderate developmental delay with lack of speech, macrocephaly, and subtle dysmorphic features including micrognathia, slightly rotated ears, and polydactyly. The karyotype of our patient was as follows: 46, XY/47, XY +mar, characterized by FISH (fluorescence in situ hybridization) using the chromosome five painting probe. Ocular involvement in trisomic 5 subjects is a very rare event. To our knowledge, only two cases have been described to date. The present case contributes to the description of the ocular presentation and the distinct clinical phenotype of de novo partial trisomy 5 syndrome.