We are all well aware of the detrimental genetic consequences of inbreeding such as hemophilia, color blindness and many other genetic disorders especially amongst British and Russian monarchies, however the impact of marriage rules on genetic diversity has never been studied.

Arranged Marriage and Its Effect on Genetic Diversity

Now a team of researchers led by Murray Cox, professor at Massey University, has examined the effects of arranged marriage on genetic diversity. This study is the first of its kind.

Given the importance at the traditional culture of the Indonesian Rindi, which marriage rules dictate at a man ideally marries his first cousin on his mother’s side in an aim to consolidate wealth and power, to study the effects – the team used a new DNA sequencing technique and a computer simulation tool known as SMARTPOP and they wanted to understand two key questions:

  • What are the expected genetic consequences of following the marriage rules?
  • From their genetic detective work, how closely do the Rindi actually follow the rules?

The team’s simulation suggests that strict adherence to this Rindi marriage should lead to a reduction in genetic diversity on the autosomes – X chromosome and mtDNA, but surprisingly, their data shows that they don’t follow rules and relaxed compliance produces a genetic diversity similar to that of random mating and their marriage rules are treated with sufficient flexibility to social connectivity with no harmful effect on biological diversity whatsoever.

The team hope with this new open-source tool they developed with SMARTPOP, researchers can now examine how other marriage rules throughout the world may affect human diversity.