A government could decide they don't like a particular phenotype and decide to visit people based on a database. Something similar happened with the harmless "what's your religion" question on census forms in the late 1930's early 1940's.
My fear, in the current era, is to be included in countless virtual 'police lineups'. The higher the availability of my DNA, the higher the chance of a false positive affecting me.
In the book a global pandemic broke out but didn't effect Muslims. How was this possible? A in-world marketing campaign promoted "Mecca Water", in which the antidote / preventative was delivered and the Muslim world was made to believe it was holy / blessed / a pilgrimage experience to consume it.
I feel it might have been a product of the post-911 world but I did find it interesting and also fear the future as it seems possible today, I'm sure some are trying.