Cytogenomic identification and long-read single molecule real-time (SMRT) sequencing of a Bardet–Biedl Syndrome 9 (BBS9) deletion

Clinical and genetic diagnosis of Bardet–Biedl syndrome. Clinical evaluation of a 14-month-old proband revealed features suggestive of BBS, including low-set ears and a right ear pit (arrow) (a), and postaxial polydactyly on the right foot (arrow) (b). Analysis of the patient specimen on the Agilent 4？×？180 CGH？+？SNP array (c, left panel) detected a single region of homozygosity at chromosome 7p14.2–p21.1. A homozygous deletion (indicated by an asterisk) of the 5′ region of BBS9 was nested within the region of homozygosity at 7p14.3. Analysis of the proband DNA with the higher-resolution Affymetrix CytoScan HD array (c, right panel) confirmed these results and further refined the deletion breakpoint