Discrepancies between the genome profile and the chromosome findings were also recorded in Case 163 where array analysis showed a genome gain of almost the whole long arm of chromosome 17 and extra copy of an ~8 Mb region at 21q22.12 containing some of the Down Syndrome Critical regions, ERG and ETS2 among other known genes (Additional file 11: Figure S8). The gene discussed is ETS2; the disease is Down syndrome.