Implex and consanguinity in your tree.

[Tolan]

The rate will depend partly on the progress of your family tree.
The more ancestors you find, the more likely it is that they are cousins.
However, common ancestors beyond the 9th generation, the consanguinity will be tiny.

The difference between implex and consanguinity:
An implex is an ancestor that is found in two places in your tree.
A consanguinity is an ancestor that is found in two places in your tree but only if they are  on the paternal side and the maternal side.
Thus, a consanguinity is necessarily an implex, but an implex is not necessarily a consanguinity.

According to my genealogical research, my implex rate is 17.32% and my consanguinity rate is 0.036%.

In my tree, I have the highest implex rate. Which is normal, since I have the most ancestors (3262) and therefore the most chance of having duplicate ancestors.

My consanguinity rate is relatively low despite the 39 consanguinity links I have. But they are too distant to be significant.

My record is for an AGP who has a consanguinity rate of 2.353%.
His parents are first cousins once removed.


And you, do you have implexes in your tree?

[Poboitz]

I haven't found an implex in my direct pedigree via paper genealogy, but that’s mainly because my ancestors didn’t take surnames until around 1800. but we only need to look back maybe 30 generations (?) until the number of ancestors on one’s tree at that generation exceeds the world population at that time. Lots of implexes!

[Kale]

Indeed, I imagine the implex rate is directly proportional to the number of generations back you go.

[Tolan]

My first implex was born in 1758.
She married twice.
My paternal GP descends from the first marriage, my paternal GM descends from the second marriage.

My closest consanguinity comes from a couple born around 1720.
I descend through 3 of their children: 2 on my mother's side, 1 on my father's side.

I also descend 6 times from a couple born around 1565 (see image).
The family ties are starting to become complicated!

[Square]

My great grand-parents on my dad side were first cousins, hence my paternal grand-father is inbred which would mean about 6 % of his chromosomes are 100 % homozygous

A quick look in the tree of my dad shows that some couple in the last 500 years are cousins, Fortunately between the range of the 5th to the 10th degrees mostly. 
Welcome in French Flanders.

I have to look deeper to calculate my implex index.

Interestingly the couple Damman X Feuts not only appear multiple times in my dad's tree but also connect to a branch of nobility that was lost among the local peasants, the "De Bersacques",well studied among expert genealogist.

https://www.academia.edu/8034433/Nouvell...Saint_Omer

Charlemagne is my ancestor multiples times, as many other living french person nowadays I suppose.

[ChrisR]

The rate will depend partly on the progress of your family tree.
The more ancestors you find, the more likely it is that they are cousins.
However, common ancestors beyond the 9th generation, the consanguinity will be tiny.

The difference between implex and consanguinity:
An implex is an ancestor that is found in two places in your tree.
A consanguinity is an ancestor that is found in two places in your tree but only if they are  on the paternal side and the maternal side.
Thus, a consanguinity is necessarily an implex, but an implex is not necessarily a consanguinity.

According to my genealogical research, my implex rate is 17.32% and my consanguinity rate is 0.036%.

In my tree, I have the highest implex rate. Which is normal, since I have the most ancestors (3262) and therefore the most chance of having duplicate ancestors.

...

And you, do you have implexes in your tree?

How do you calculate your implex rate and consanguinity rate?
I normally do not work with, but tried Gramps with some Python script, but had not enough time and knowledge to get what would interest me:

From a given person for all ancestors and for every ancestral generation:
- researched ancestors: count and %
- unresearched ancestors: count and %
- implex: count and %
- unique ancestors: count and %
- consanguinity: count and %
- Endogamous marriages (same place/village)
- Average Age at marriage: male and female
- Average Age at birth of ancestor: father and mother

I would like to research regarding genetics:
average genetic ancestors per ancestral generation, Genetic diversity (heterozygosity), Runs of Homozygosity (ROH), Genetic relatedness (IBD, shared cM length);
The following I noted but think they are not interesting for a small family focused research: α average consanguinity coefficient, Ft inbreeding coefficient at time _t_, Fr inbreeding coefficient due to random mating within a finite population, Fn inbreeding coefficient due to non-random mating, RP random isonymy value (sharing of surnames), RPr random isonymy value taking into account the population's finite size, (Rp-RPr)/RPr standardized measure of the deviation of observed isonymy (RP) from the expected isonymy under random mating in a finite population

[ChrisR]

I haven't found an implex in my direct pedigree via paper genealogy, but that’s mainly because my ancestors didn’t take surnames until around 1800. but we only need to look back maybe 30 generations (?) until the number of ancestors on one’s tree at that generation exceeds the world population at that time. Lots of implexes!

I do have implex I think beginning from 5th or 6th ancestral generation onwards.
Regarding the relation of implex, genetic ancestors, inherited sequence size and living population at a given time in the last week I had a discussion on another forum in another language where we came up with some interesting research and numbers:

ancestral generations ago; genetic ancestors per parent; inherited ancestral sequence per parental chromosome set (IBD); implex
25-50; ; 6-7 cM; >99.9% [disputed]
70; ca. 2485; ca. 1.4 cM;
100; ca. 3550; ca. 1 cM

See also the Pedigree collapse - Wikipedia quote
"If one considers as a function of time t the number of a given individual’s ancestors who were alive at time t, it is likely that for most individuals this function has a maximum at around 1200 AD."
And Whole-genome sequence variation, population structure and demographic history of the Dutch population

[FionnSneachta]

Nothing to brag about but two of my great grandparents were second cousins who married each other. It is what it is. They had nine healthy children which is the main thing so no harm done I guess. The children mostly reached good ages too as long as they didn't get cancer. They were 82, 72, 92, 77, 90, 82, 57, and 80. One of them is still alive and she is 98 (born the same year as the Queen and has obviously passed her out). I haven't found any other duplicate ancestors in my tree but it's only going back to the late 1700s.

[Tolan]

The rate will depend partly on the progress of your family tree.
The more ancestors you find, the more likely it is that they are cousins.
However, common ancestors beyond the 9th generation, the consanguinity will be tiny.

The difference between implex and consanguinity:
An implex is an ancestor that is found in two places in your tree.
A consanguinity is an ancestor that is found in two places in your tree but only if they are  on the paternal side and the maternal side.
Thus, a consanguinity is necessarily an implex, but an implex is not necessarily a consanguinity.

According to my genealogical research, my implex rate is 17.32% and my consanguinity rate is 0.036%.

In my tree, I have the highest implex rate. Which is normal, since I have the most ancestors (3262) and therefore the most chance of having duplicate ancestors.

...

And you, do you have implexes in your tree?

How do you calculate your implex rate and consanguinity rate?
I normally do not work with, but tried Gramps with some Python script, but had not enough time and knowledge to get what would interest me:

From a given person for all ancestors and for every ancestral generation:
- researched ancestors: count and %
- unresearched ancestors: count and %
- implex: count and %
- unique ancestors: count and %
- consanguinity: count and %
- Endogamous marriages (same place/village)
- Average Age at marriage: male and female
- Average Age at birth of ancestor: father and mother

I would like to research regarding genetics:
average genetic ancestors per ancestral generation, Genetic diversity (heterozygosity), Runs of Homozygosity (ROH), Genetic relatedness (IBD, shared cM length);
The following I noted but think they are not interesting for a small family focused research: α average consanguinity coefficient, Ft inbreeding coefficient at time _t_, Fr inbreeding coefficient due to random mating within a finite population, Fn inbreeding coefficient due to non-random mating, RP random isonymy value (sharing of surnames), RPr random isonymy value taking into account the population's finite size, (Rp-RPr)/RPr standardized measure of the deviation of observed isonymy (RP) from the expected isonymy under random mating in a finite population

I use ancestris. https://www.ancestris.org/index.html
For each person in my tree, I can have the statistics of their ancestors.

Unfortunately, it rounds and when the coefficient is too low, it returns 0%.

For this person in my tree, for the consanguinity, I had to add the values from "la liste des ancêtres communs pour le coefficient de consanguinité":

[Pylsteen]

Does the implex calculation only take into account known ancestors or also unknown ones? I mean, if I go back 12 generations, I know I have a maximum of 2004 unique ancestors occupying the 2048 theoretical possible positions, but I don't know the names of about half of them... there may be many more doubles among the unknown ancestors.

[Rufus191]

The rate will depend partly on the progress of your family tree.
The more ancestors you find, the more likely it is that they are cousins.
However, common ancestors beyond the 9th generation, the consanguinity will be tiny.

The difference between implex and consanguinity:
An implex is an ancestor that is found in two places in your tree.
A consanguinity is an ancestor that is found in two places in your tree but only if they are  on the paternal side and the maternal side.
Thus, a consanguinity is necessarily an implex, but an implex is not necessarily a consanguinity.

According to my genealogical research, my implex rate is 17.32% and my consanguinity rate is 0.036%.

In my tree, I have the highest implex rate. Which is normal, since I have the most ancestors (3262) and therefore the most chance of having duplicate ancestors.

My consanguinity rate is relatively low despite the 39 consanguinity links I have. But they are too distant to be significant.

My record is for an AGP who has a consanguinity rate of 2.353%.
His parents are first cousins once removed.


And you, do you have implexes in your tree?

It is an interesting subject. I guess people alive today would be less likely to have a higher consanguinity rate, since the taboo against cousin marriages, and also simply the social, geographical and migratory structures that encouraged it are now broken down to some greater extent for a large proportion of the population. But there are many people that still have parents who basically come from a similar or same area and inevitably if their pedigrees are traced correctly (and DNA verified) you may find cases like AGP.  I can say, being of mostly protestant British descent, when you go back into the 19th century, marriage of cousins seems fairly common, but, at least in my family, fairly largely outnumbered by marriages 'out'. One thing I noticed was widows and widowers often ended up marrying a cousin, possibly somewhat marriages of convenience - the man needed someone to look after his household and bring up his children if he had them, and a woman needed a breadwinner, protector and provider for hers. Perhaps cousins were the 'quick' and 'safe' option rather than extended period of attempts at courting. In cases where widowhood was not involved, maybe they were seen as not making much headway or expressing much interest in courting the opposite sex and maybe some pressure was put on within the families to marry off the unmarried. 
  As far as I know my consanguinity rate is 0, but my mother's paternal grandparents were 2nd cousins, and on another side her great grandfather's parents' were 1st cousins. The 2nd cousin marriage was due to them being part of a religious sect, and the 1st was simply that they were a rural family of very long standing origins in the same area (at least 450 years). So my grandfather would have 232 great x 7 grandparents instead of 256. But a cousin, still alive, also who descends from this religious sect only has 192. I also have a marriage of 1st cousin ancestors at a similar period on my father's side, in similar rural circumstances, his great x 3 grandparents. Also on my father's side, it turned out my grandfather's aunt married her 1st cousin in the 1890s, and he never spoke of this line or this aunt and uncle at all, so maybe there was an element of embarassment about it in 20th century eyes.

[ChrisR]

The rate will depend partly on the progress of your family tree.
The more ancestors you find, the more likely it is that they are cousins.
However, common ancestors beyond the 9th generation, the consanguinity will be tiny.

...

According to my genealogical research, my implex rate is 17.32% and my consanguinity rate is 0.036%.

In my tree, I have the highest implex rate. Which is normal, since I have the most ancestors (3262) and therefore the most chance of having duplicate ancestors.

My consanguinity rate is relatively low despite the 39 consanguinity links I have. But they are too distant to be significant.

My record is for an AGP who has a consanguinity rate of 2.353%.
His parents are first cousins once removed.

Thanks to the hint to Ancestris I could do the calculation for my RSGen Genealogy:
6044 ancestors up to 34 generations distance researched, 100% until the 7th ancestral generation, 83.2% of the 10th ancestral generation, 4.66% of the 15th ancestral generation.
implex rate is 61.41% and consanguinity rate is 0.0001543
98 implex ancestors, 13 ancestors responsible for the consanguinity rate
The highest cansanguinity rate is 0.01563 for an ancestor in the 9th ancestral generation.

[wing genealogist]

I descend almost exclusively from "Great Migration" Colonists to New England 1620-1660. I have also been fortunate to be able to trace many of my lines back to my immigrant ancestor. As such, I have been able to determine that all eight of my great-grandparents are related to each other and going one generation further back I only have a single pair among my 16 great-great-grandparents where I could not find a relationship.

Most of these relationships are quite distant, but on my mother's side she descends from two daughters of a first cousin marriage as well as other lines from the same family (Burns family of Embden, Maine). My mother descends six different ways from James Burns & Abigail Spencer (married in 1768). She also has double relationships to the Berry, Moulton and Williams families of Embden.

While much more distant, on my father's side I descend from Rev. Stephen Bachiler (the "father of New Hampshire") from ALL of his children who left descendants in New England: son Nathaniel and daughters Deborah (m. Rev. John Wing), Ann (m. ---- Samborne) and Theodate (m. Christopher Hussey). My father also has some doubled lines such as Norcross and Huff.

To give an indication of how far back I have been able to trace my ancestry in New England, seven of my eight great-grandparents descend from one or more Mayflower passengers.