This Mummified Corpse Is The Great-Great-Great-Great-Great-Great-Great-Grandmother Of Boris Johnson

    Scientists say a body uncovered in 1975 is in fact the great-great-great-great-great-great-great-grandmother of the UK foreign secretary.

    Boris Johnson has said he's proud to be the distant descendant of a woman whose mummified corpse has baffled scientists since she was discovered in a Swiss church more than 40 years ago.

    On Wednesday it emerged that a body, found in a Basel church during renovations in 1975, is that of Anna Catharina Bischoff, a wealthy woman who was born in 1719 and died in 1789. She was buried in front of the church's altar. She is Johnson's great-great-great-great-great-great-great-grandmother.

    Very excited to hear about my late great grand 'mummy' - a pioneer in sexual health care. Very proud https://t.co/9EKLPlzfk8

    Author and journalist Rachel Johnson, Boris' sister, also acknowledged her distant ancestor.

    Swiss woman who died in 1787 is still defined by her relationship to living male relative https://t.co/Uhr2SQ75Ry

    As the BBC reports, DNA taken from her toe has shown she was a member of the Bischoff family – it had a 99.8% match with DNA taken from living descendants of the Bischoffs.

    Anna Catharina Bischoff had seven children but only two survived to adulthood – one of them, Anna, married Christian Hubert Baron Pfeffel von Kriegelstein.

    Several generations later, Alexander Boris de Pfeffel Johnson was born, and is now the UK's foreign secretary and Conservative MP for Uxbridge and South Ruislip.

    Scientists believe Bischoff may have been treated for syphilis, after finding high levels of mercury in her body, a common 18th-century cure for sexually transmitted diseases. It may not have worked, but the mercury did help to preserve her body.

    The revelations are due to be shown in a documentary by Swiss broadcaster SRF on Thursday night.