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.