Funding for this research was provided by:
National Human Genome Research Institute (U01HG008222)
Received: 6 April 2017
Accepted: 19 February 2018
First Online: 27 February 2018
Ethics approval and consent to participate
: Ethics approval was obtained from the Research Ethics Committees at Stellenbosch University (N14/02/010) and the University of Cape Town (O84/2016).Written consent was obtained from all respondents.
: Not applicable
: The authors declare that they have no competing interests.
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