North Delta, and the donors a registry does not have

The City of Delta is made up of three communities — North Delta, Ladner and Tsawwassen — and the city's own community profile calls North Delta the most populous of the three. That profile, built on 2021 census data, counts 61,499 people living here, about 57 per cent of Delta's total population of 108,455. Day 17 is eleven miles of ordinary suburban walking: side streets, arterials, school zones, the sort of ground that makes up most of a forty-five-day route.

That same profile records the most common racialized groups counted in North Delta in 2021: South Asian residents at 41 per cent of the population, Chinese residents at 10 per cent, and Filipino residents at 4 per cent. Those numbers are the reason this leg goes through the neighbourhood instead of past it.

The reason the numbers matter at all is a piece of biology. Patients and donors are matched on HLA — the tissue-type markers a transplant team compares — and HLA is inherited. NMDP explains that half of yours comes from your mother and half from your father. Because those markers travel down family lines, ancestry travels with them. Canadian Blood Services puts it in a single sentence: people are more likely to find a stem cell match with a donor of similar ancestral or ethnic background. Only about a quarter of patients find a match inside their own family. The other three-quarters are searching a list of strangers.

And a list of strangers can only offer the strangers it has. Where a community is thinly represented on the registries, fewer of its patients find a match — not because the medicine failed but because the name was never on the list. That is the argument for a walk that goes through neighbourhoods rather than around them. The Jada Bascom Foundation does not run a registry, does not type anyone's cells and does not mail swab kits; it points people toward the registries that do.