A brother and sister's search for a bone marrow match for their mother has led to a jump in the number of Jewish people joining the Anthony Nolan Trust.
Jonni, 34, and Caroline Berger, 31, appealed on Twitter - #spit4mum - after Sharon Berger was told she needed an urgent bone marrow transplant in weeks.
Mrs Berger, 61, of Harrow, north-west London, has myelodysplastic syndrome.
Finding a match is proving difficult because of her best match is likely to be another Ashkenazi Jew.
The charity said 180 Jewish people signed up in the first two weeks of 2013, up from 31 in January 2012.
Read more: http://www.bbc.co.uk/news/uk-england-london-21089305