Array-based comparative genomic hybridization in 190 Korean patients with developmental delay and/or intellectual disability: a single tertiary care university center study.

[22q11.2 deletion syndrome]

This study analyzed and evaluated the demographic , clinical , and cytogenetic data [G-banded karyotyping and array-based comparative genomic hybridization (array CGH )] of patients with unexplained developmental delay or intellectual disability at a single Korean institution .We collected clinical and cytogenetic data based on retrospective charts at Ajou University Medical Center , Suwon , Korea from April 2008 to March 2012 .A total of 190 patients were identified . Mean age was 5 .1 Â±1 .87 years . Array CGH yielded abnormal results in 26 of 190 patients (13 .7 %). Copy number losses were about two-fold more frequent than gains . A total of 61 .5 % of all patients had copy number losses . The most common deletion disorders included 22 q 11 .2 deletion syndrome , 15 q 11 .2 q 12 deletion and 18 q deletion syndrome . Copy number gains were identified in 34 .6 % of patients , and common diseases among these included Potocki-Lupski syndrome , 15 q 11 -13 duplication syndrome and duplication 22 q . Abnormal karyotype with normal array CGH results was exhibited in 2 .6 % of patients ; theses included balanced translocation (n =2 ), inversion (n =2 ) and low -level mosaicism (n =1 ). Facial abnormalities (p <0 .001 ) and failure to thrive were (p <0 .001 ) also more frequent in the group of patients with abnormal CGH findings .Array CGH is a useful diagnostic tool in clinical settings in patients with developmental delay or intellectual disability combined with facial abnormalities or failure to thrive .