Inbreeding may have led to the demise of the Hapsburgs

A new study by geneticists from the University of Santiago de Compostela, Spain shows that inbreeding may have weakened the male line and brought about the end of the Hapsburg dynasty. The last king, Charles II of Spain, died in 1700 without male heirs.

The scientists looked at genetic evidence of "3,000 of his relatives and ancestors across 16 generations" to determine that the common ancestry of both parents increased considerably down the generations. "Based on this clinical genetic knowledge and on information gathered by historians on the health of Charles II, Alvarez and colleagues speculate that the simultaneous occurrence of two different genetic disorders (combined pituitary hormone deficiency and distal renal tubular acidosis), determined by recessive alleles at two unlinked loci, could explain much of the complex clinical profile of this king, including his impotence/infertility, which led to the extinction of the dynasty."