You don't need a matchmaker, just your HLA genes, or so goes the idea at Switzerland's GenePartner, which is building on the small evidence that people are attracted to others with different HLA genes than their own. The company says that by seeing what versions of HLA genes a couples has, it can tell whether the relationship is doomed or has a chance. The company also offers the test to singles who can then add their rating into an online dating profile.