Mrs Berger, 61, from from Harrow, north-west London, suffers from myelodysplastic syndrome and has a combination of rare tissue types, making finding a matching donor more difficult.

BBC: Caroline and Sharon Berger

Asians are also more likely to have diverse tissue types, which makes finding a matching donor harder.

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Mrs Berger, from Harrow, north-west London, has a combination of rare tissue types that has made finding a matching donor more difficult.

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