Abstract:
The presence of founder effects in South Africa for many
single-gene diseases, which include heart diseases such as
progressive familial heart block types I and II, hypertrophic
cardiomyopathy and the long QT syndromes, afforded us the
opportunity to identify causal genes and associated mutations
through genetic mapping and positional cloning. From
finding the genes, the emphasis has shifted to elucidating how
primary defects cause disease and recognising factors that
could explain the often pronounced phenotypic variability
seen in persons carrying the same inherited defect. In some of
these diseases, sudden unexpected death has been a frequent
occurrence in young, apparently healthy individuals who had
not been aware that they had inherited an underlying risk.
Herein, we review progress in identifying genes, mutations
and risk factors associated with the diseases mentioned.
