She is the Director of the AfriCenter division of the ISAAA, a non-profit international organization that shares agricultural biotechnology, focusing on genetic engineering.

In 2000 her project involving the evaluation and transfer of tissue culture banana technology to the benefit of more than 5,000 farmers in East Africa was awarded the First Research Medal in the Global Development Network (GDN) awards for ‘Science and Technology for Development’ sponsored by the Government of Japan and the World Bank.

In 2001, as a staff member of the Kenyatta University, she was interviewed by New Scientist magazine regarding the propaganda from certain green organisations about biotechnology in Europe that has led to obstruction of attempts to combat hunger in Africa.

[4] In 2014 she wrote an opinion piece for the International Food Policy Research Institute published on SciDev.net entitled: The problems with the arguments against GM crops in which she pointed out that by 2013 more than 18 million farmers (at least 90 per cent of which were small-scale resource-poor farmers in developing countries) had chosen to use genetically modified crops on more than 175 million hectares of farmland.

“Contrary to widely held opinion that GM technology will only benefit multi-nationals and is meant for large-scale farmers, the latest trends reveal otherwise.”[5][6] Karembu has actively promoted low-environmental impact methods, biotechnology sharing and genetically modified organisms as part of her work, by writing papers, presenting at conferences,[7][8][9] writing two books for children presenting the case for genetically modified crops and in many interviews.

During Session VI: Food Biotechnology, she said that the voices of African scientists have been overshadowed by those of human rights activists who are opposed to GMOs.