Application of Array CGH technique for the clinical diagnosis of developmental delay and congenital malformations in Saudi Arabia [400k]

Chromosomal imbalances are implicated in the etiology of developmental delay (DD) and congenital malformation (CM). We therefore conducted high resolution array comparative genomic hybridization (array CGH) of sixty three Saudi patients [11 by Agilent-001850/CGH1x244A and 52 by Agilent-014693/CGH2x400k] for investigating and understanding the genetic heterogeneity underlying DD/CM. A total of 76 disease associated copy number variants (CNVs) were detected in twenty four patients including 1p36, 1q21, 3p23, 6p24, 7q11, 8q24, 9q33, 10p14, 11p15, 11q12, 11q24, 13q21, 15q13, 16p13, 18q23, trisomy 18, 20q11, 21q22, 22q11.21, 47,XXY and 45,X0. The diagnosis rate of array CGH was 2.6 times higher than karyotyping. A total of 63 patients with developmental delay (DD) and congenital malformation (CM) were recruited for the study. Agilent Euro of homo sapines were used reference DNA [Male and Female: Part No 5190-3796 and 5190-3797]. To investigate genome defects, we applied high-density array CGH using SurePrint G3 Human CGH Microarray Kit, 1x244 K and 2x400 K, consisting of 244,000 and 400,000 copy number probes respectively (Agilent Technologies, Santa Clara, California, USA) using UCSC hg18 reference genome.