Table 1 Samples and corresponding DNA extraction strategy.

Breast: tumour and normal

Molzym Ultradeep Microbiome (Molzym, Bremen, Germany)

Oesophageal biopsies

AllPrep DNA/RNA Mini Kit (Qiagen, Hilden, Germany) with modifications¹⁰

Skin Swab samples

QIAamp UCP Pathogen Mini Kit (Qiagen, Hilden, Germany)

Stool samples

Repeated bead beating method as previously described, with modifications^{11, 12}