Culture, General Things, Coefficient of Inbreeding, COI 25% and Higher

COI 25% and Higher. An individual who is the child of brother and sister, or father and daughter, or mother and son, or equivalent to.

The best known case of individuals with a COI higher than 25 is the five children of Philip IV King Spain and Mariana of Austria Queen Consort Spain who had a COI of 25.39% going back ten generations with fifty-three common ancestors (see study undertaken by the University of Santiago de Compostela in Jan 2010). Taking their ancestry back further to eighteen generations they have a COI of 25.89% with two hundred and sixty four common ancestors.

Of the five children one died after 14 days, one died aged nearly four years old, one died aged nine months. Two, Charles "Bewitched" II King Spain and Margaret Theresa Habsburg Holy Roman Empress, grew to adulthood.

Only one had children, Margaret Theresa Habsburg Holy Roman Empress, who married her uncle and cousin Leopold Habsburg Spain I Holy Roman Emperor. They had four children of which one died the day they were born, one died after fourteen days, one died aged three months and one, Maria Antonia of Austria, who had a COI of 30.98 died aged nearly twenty-three years having given birth to three children two of whom died at birth and one died aged seven years.

On 9th February 1672 Maria Anna Antonia Habsburg Spain was born to Leopold Habsburg Spain I Holy Roman Emperor (age 31) and Margaret Theresa Habsburg Holy Roman Empress (age 20). She died on 23rd February 1672 aged two weeks. Coefficient of inbreeding 30.98%.

On 18th January 1669 Maria Antonia of Austria was born to Leopold Habsburg Spain I Holy Roman Emperor (age 28) and Margaret Theresa Habsburg Holy Roman Empress (age 17). Coefficient of inbreeding 30.98%.

On 20th February 1670 Johann Leopold Habsburg Spain was born to Leopold Habsburg Spain I Holy Roman Emperor (age 29) and Margaret Theresa Habsburg Holy Roman Empress (age 18). He died the same day. Coefficient of inbreeding 30.98%.

On 28th September 1667 Ferdinand Wenzel Habsburg Spain was born to Leopold Habsburg Spain I Holy Roman Emperor (age 27) and Margaret Theresa Habsburg Holy Roman Empress (age 16). On 13th January 1668 Ferdinand Wenzel Habsburg Spain died. Coefficient of inbreeding 30.98%.

In 142BC Ptolemy IX Soter 142BC 81BC was born to Ptolemy VIII Physcon 184BC 116BC (age 42) and Cleopatra III 160BC 101BC (age 18). Coefficient of inbreeding 28.54%.

Around 138BC to 135BC Cleopatra IV 138BC 112BC was born to Ptolemy VIII Physcon 184BC 116BC (age 46) and Cleopatra III 160BC 101BC (age 22). Coefficient of inbreeding 28.54%.

Around 135BC to 130BC Cleopatra Selene of Syria 135BC 130BC was born to Ptolemy VIII Physcon 184BC 116BC (age 49) and Cleopatra III 160BC 101BC (age 25). Coefficient of inbreeding 28.54%.

Ptolemy VII Neos Philopator was born to Ptolemy VIII Physcon 184BC 116BC and Cleopatra II 186BC 115BC. Coefficient of inbreeding 28.54%.

Around 160BC to 155BC Cleopatra III 160BC 101BC was born to Ptolemy VI 186BC 145BC (age 25) and Cleopatra II 186BC 115BC (age 26). Coefficient of inbreeding 28.54%.

Tryphaena was born to Ptolemy VIII Physcon 184BC 116BC and Cleopatra III 160BC 101BC. Coefficient of inbreeding 28.54%.

In 140BC or 139BC Ptolemy X Alexander I 140BC 88BC was born to Ptolemy VIII Physcon 184BC 116BC (age 44) and Cleopatra III 160BC 101BC (age 20). Coefficient of inbreeding 28.54%.

John Armagnac was born illegitimately to Jean V Count Armagnac and Isabelle Armagnac. Coefficient of inbreeding 27.06%.

Anthony "Bastard" Armagnac was born illegitimately to Jean V Count Armagnac and Isabelle Armagnac. Coefficient of inbreeding 27.06%.

Rose Armagnac was born illegitimately to Jean V Count Armagnac and Isabelle Armagnac. Coefficient of inbreeding 27.06%.

On 9th October 210BC Ptolemy V Epiphanes 210BC 180BC was born to Ptolemy IV Philopator 244BC 204BC (age 34) and Arsinoe III 246BC 204BC (age 36). Coefficient of inbreeding 26.66%.

On 7th December 1655 Maria Ambrosia Habsburg Spain was born to Philip IV King Spain (age 50) and Mariana of Austria Queen Consort Spain (age 20). She died 14 days later. Coefficient of inbreeding 25.39%.

On 28th November 1657 Philip Prospero Habsburg Spain Prince Asturias was born to Philip IV King Spain (age 52) and Mariana of Austria Queen Consort Spain (age 22). He died four years later. Coefficient of inbreeding 25.39%.

On 23rd December 1658 Ferdinand Thomas Charles Habsburg Spain was born to Philip IV King Spain (age 53) and Mariana of Austria Queen Consort Spain (age 24). He died ten months later. Coefficient of inbreeding 25.39%.

On 12th July 1651 Margaret Theresa Habsburg Holy Roman Empress was born to Philip IV King Spain (age 46) and Mariana of Austria Queen Consort Spain (age 16). Coefficient of inbreeding 25.39%.

Around 1630 Mary Cornwall Lady Reade was born to Gilbert Cornwall 13th Baron Burford (age 32) and Anne Lyttelton Baroness Burford (age 61). Coefficient of inbreeding 25.00%.

Around 1341BC Tutankhamun 1341BC 1323BC was born to Akhenaten KV55 1336BC and The Younger Lady. Coefficient of inbreeding 25.00%.

On 28th January 1618 James Ley 3rd Earl Marlborough was born to Henry Ley 2nd Earl of Marlborough (age 22) and Mary Pettie. Coefficient of inbreeding 25.00%.

Henrietta Molesworth was born to Richard Molesworth 3rd Viscount Molesworth and Letitia Coote. Coefficient of inbreeding 25.00%.