[1] Groote Schuur Hosp, Dept Med, Neurol Res Grp, ZA-7925 Cape Town, South Africa
[2] Univ Cape Town, Fac Hlth Sci, Div Human Genet Clin & Lab Sci, ZA-7925 Cape Town, South Africa
[3] Univ Western Cape, S African Natl Bioinformat Inst, Bellville, South Africa