The Mother’s Curse’ that Endured for Centuries
A mutation that is inherited maternally, and causes vision loss mostly in men, persisted in a family for at least 290 years — a rare example of an evolutionary phenomenon known as ‘the mother’s curse’.
Most animals inherit their mitochondria, the powerhouses of cells, from their mother.
A team led by Emmanuel Milot at the University of Quebec at Trois-Rivières in Canada traced the inheritance of a mitochondrial disease called Leber’s Hereditary Optical Neuropathy (LHON) in 2,038 members of an extended French–Canadian family between 1670 and 1960.
Genealogy records show that the disease was first recorded in the family of a woman who arrived in Quebec from France in the 1600s. As well as experiencing vision loss, male descendants who inherited her mutation were much more likely to die in infancy than non-carriers and females.
This deadly mutation would have been vanquished by natural selection, the researchers say, had it not been spread along the maternal line.