Interstitial 4q Deletion and Isodicentric Y-Chromosome in a Patient with Dysmorphic Features.

We present a 2-year-old boy with a de novo 46,XY,idic(Y)(q11.221),del(4)(q26q31.1) karyotype. G-banding, FISH, MLPA, and SNP-array techniques were used to characterize the 24-Mb deletion in 4q and the breakpoint in the isodicentric Y-chromosome region between 15,982,252 and 15,989,842 bp. The patient presented with mild facial dysmorphism, hemangioma, mild frontal cerebral atrophy, and Dandy-Walker variant. Essentially, this case reveals that patients can present more complex genomic imbalances than initially suspected.