age: 4 years gender: Female phenotype: Developmental delay and Obesity, Congenital Heart Disease, Normal Milestones tissue: Peripheral Blood
Treatment protocol
Not Applicable
Growth protocol
Not Applicable
Extracted molecule
genomic DNA
Extraction protocol
DNA was extracted after harvesting the cells by Trypsin (Invitrogen) followed by phenol-chloroform extraction and subsequent precipitation in 100% ethanol. DNA precipitate was washed with 70% ethanol then eluted in DNAse free water.
Label
Cy3
Label protocol
Labelling was performed using the Agilent Genomic DNA Labeling Kit PLUS (Agilent Technologies, Inc., Palo Alto, USA) according to the manufacturer’s directions. Briefly, DNA was labelled with 1.5 - 3 mM Cy3-dUTP (Agilent Technologies, Inc., Palo Alto, USA), and purified using a Centricon YM-30 filter (Millipore, Billerica, USA).
DNA was extracted after harvesting the cells by Trypsin (Invitrogen) followed by phenol-chloroform extraction and subsequent precipitation in 100% ethanol. DNA precipitate was washed with 70% ethanol then eluted in DNAse free water.
Label
Cy5
Label protocol
Labelling was performed using the Agilent Genomic DNA Labeling Kit PLUS (Agilent Technologies, Inc., Palo Alto, USA) according to the manufacturer’s directions. Briefly, DNA was labelled with 1.5 - 3 mM Cy3-dUTP (Agilent Technologies, Inc., Palo Alto, USA), and purified using a Centricon YM-30 filter (Millipore, Billerica, USA).
Hybridization protocol
Probe mixture of Cy3-labelled sample DNA, Cy5-labelled reference DNA, 50 μl of 1.0mg/ ml of human Cot-1 DNA (Invitrogen, USA), 52 μl of Agilent 10X Blocking Agent and 260 μl of Agilent 2X Hybridization Buffer (Part/Cat No of human reference DNA Male and Female: 5190-3796 and 5190-3797, Agilent Technologies, Inc.) was denatured at 100C for 1 minute 30 seconds and incubated at 37C for 30 minutes. The probe was applied to the array using an Agilent microarray hybridization chamber, and hybridized for 40 hours at 65C in a rotating oven (Robbins Scientific, Sunnyvale, USA) at 20 rpm. Arrays were washed according to the manufacturer’s recommendation and air dried.
Scan protocol
Arrays were scanned using an Agilent 2565AA DNA microarray scanner (Agilent Technologies, Inc).
Description
Developmental delay and Obesity, Congenital Heart Disease, Normal Milestones
Data processing
Data were processed using Agilent’s Feature Extraction software protocol for array-CGH data. To analyze genomic imbalance tumour samples (2 arrays each) the processed R signal and processed G signal columns from the Agilent Feature Extraction-generated a-CGH .txt files were imported into PGS. The tumour-specific signal across all probes was normalized as a ratio to baseline using Normalise to Baseline Tool in PGS, where baseline data corresponded to the normal human DNA. The data was then log2 transformed using the PGS Normalization and Scaling Tool. In order to detect regions of genomic gain and loss we applied the Genomic Segmentation tool with segmentation parameters set at: min. probes: 10, p-value threshold: 0.01, and signal to noise: 0.1. Region report was set at values bellow -.5/+.5 (log2) and p-value threshold of 0.05 for 2/2 (replicate) arrays in individual analysis or at 40% cut-off in cumulative analysis (i.e. 4/10 tumour samples). Regions of significant gain or loss were annotated to the corresponding genes present on the Affymetrix Gene 1.0 Array using the HuGene-1_0-st-v1.na24.hg18.transcript.csv file. Visualizations and VENN analysis were performed in PGS.
