Sample Collection

Sample collection

Prior to the volunteer’s visit for colonoscopy volunteers are given verbal and written advice on how to prepare for colonoscopy, which includes bringing in doctor’s office their: (a) faecal sample on ice, (b) full blood test exams; and (c) the pertinent filled in questionnaire.

During the volunteer’s visit for colonoscopy:

● The doctor will collect a blood sample just before anaesthesia for colonoscopy. Processing involves: (i) the separation of serum from WBCs, (ii) DNA extraction from WBCs, and (iii) storage of
serum and DNA at -80 °C.
● During colonoscopy the doctor collects 10 pinch biopsies (10-20mg each) of Normal-Appearing Mucosa (at least 15cm away from any tumour): two from the rectum, two from the sigmoid colon, two from the descending colon, two from the transverse colon, and two from the ascending colon.
● Biopsies are added in pre-weighed, pre-labelled (6-digit coded and dated) 2 ml RNase, DNase free tubes, containing 200μl 0.1mm zirconium beads, and immediately immersed in liquid nitrogen (-200 °C) or covered in dry ice (-80 °C) and stored at -80 °C at the UCY Biobank after weighing. Upon processing DNA samples are stored at -20 °C, while RNA and protein samples at -80 °C.
● The doctor removes and places in formalin any tumours found, which are subsequently assessed histopathologically.
● All samples and data are anonymized before any cataloguing and analysis.