ABSTRACT
Deletions of the short arm of chromosome 19 are rarely found by conventional cytogenetic techniques. This region has a high gene density and this is likely the reason why deletions in this region are associated with a severe phenotype. Since the implementation of modern high-resolution SNP- and CGH-array techniques more cases have been reported. Here, we present an almost 5-year-old boy with intellectual disability, minor dysmorphisms, febrile seizures, and a de novo deletion of 834.2 kb on 19p13.2 encompassing 32 genes. The deletion was found by the Illumina Infinium HD Human1M-Duo v1 BeadChip SNP-array and confirmed by the NimbleGen Human CGH 2.1M Whole Genome Tiling v2.0D oligonucleotide array. PCR amplification of the junction fragment and subsequent sequencing defined the breakpoints and indicated that formation was mediated by non-allelic homologous recombination (NAHR). The phenotype of our patient shows that microrearrangements even at gene-dense chromosomes may result in mild clinical consequences.
