Author Topic: DNA - summary - worth it?  (Read 1601 times)

Offline DianaCanada

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Re: DNA - summary - worth it?
« Reply #45 on: Thursday 20 March 25 10:16 GMT (UK) »

The only thing a  DNA tree is is a mapping of DNA relationships of those whose DNA has been tested and match with you.  Unless all people have tested it can only be  partial and, even then,  we know that DNA is not distributed in an ordered way. It is also, by definition, shallow after a number of generations.

What is achieved by this narrow approach?  It seems to me that it reduces our humanity in favour of a breeders' stock book of animal pedigrees. 


It certainly is useful for those who want to find biological parents, grandparents, etc.  I was always left feeling there was something missing by not knowing who my grandfather was (but not my great-great grandfather , that was just curiosity).  A breeder’s stock book? That’s a little harsh.  My grandparents had some kind of relationship, and my mother’s subsequent birth influenced her life enormously, and in some ways, mine too.


Offline Gadget

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Re: DNA - summary - worth it?
« Reply #46 on: Thursday 20 March 25 10:24 GMT (UK) »
I think you've mixed up your paragraph in the quote, Diana

I wrote:


The only thing a  DNA tree is is a mapping of DNA relationships of those whose DNA has been tested and match with you.  Unless all people have tested it can only be  partial and, even then,  we know that DNA is not distributed in an ordered way. It is also, by definition, shallow after a number of generations.

What is achieved by this narrow approach?  It seems to me that it reduces our humanity in favour of a breeders' stock book of animal pedigrees. 

We are social animals and the resulting family bonds are primarily social not genetic.

You stated:

Quote
It certainly is useful for those who want to find biological parents, grandparents, etc.  I was always left feeling there was something missing by not knowing who my grandfather was (but not my great-great grandfather , that was just curiosity).  A breeder’s stock book? That’s a little harsh.  My grandparents had some kind of relationship, and my mother’s subsequent birth influenced her life enormously, and in some ways, mine too.

I agree that for  finding an unknown relative via the DNA route is of use. I found my great grandfather using DNA matches, but the subsequent route was by researching these matches via their social family ties.
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Offline melba_schmelba

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Re: DNA - summary - worth it?
« Reply #47 on: Thursday 20 March 25 10:28 GMT (UK) »

The only thing a  DNA tree is is a mapping of DNA relationships of those whose DNA has been tested and match with you.  Unless all people have tested it can only be  partial and, even then,  we know that DNA is not distributed in an ordered way. It is also, by definition, shallow after a number of generations.

What is achieved by this narrow approach?  It seems to me that it reduces our humanity in favour of a breeders' stock book of animal pedigrees. 

We are social animals and the resulting family bonds are primarily social not genetic.
Also, from the simple statistics that we know about, and also the laws of DNA inheritance, there comes a point, with anyone who is, say researching ancestors before 1750, that you are more likely than not to share no DNA of that ancestor that you are looking at. Does that mean there is no point in being interested? Of course that is not the case. And even people here who might take the only DNA matters point of view, I bet still trace what they think is the correct DNA line and carrying on tracing back as far as they can!
  Some time ago, there was a discussion about the likelihood of eventually any ancestral line, on the male line, originating with someone of another surname than was passed down on that male line. But none of us could really agree on the maths ;D! So I just asked AI....

To calculate the likelihood that in one of the 10 generations the father was someone other than was known, given a 4% chance per generation, we can use the concept of complementary probability.

The probability that the father is the known individual in any given generation is 1−0.04=0.96.

The probability that the father is the known individual in all 10 generations is 0.9610.

Therefore, the probability that in at least one of the 10 generations the father was someone other than was known is:

1−0.9610 ≈1−0.6648=0.3352

So, the likelihood that in one of those 10 generations the father was someone other than was known is approximately 33.52%.


So everyone has 1/3 chance that by 10 generations back, your male line originated with someone of a different surname.

Offline Gadget

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Re: DNA - summary - worth it?
« Reply #48 on: Thursday 20 March 25 10:41 GMT (UK) »
Many years ago, I was an MRC Research Officer. Our research area was to examine family patterns. My interest was in the field of infertility - couples who had fertility problems. I interviewed many couples and listened to their description of attempts to have children - fertility treatment, adoption or IVF by donor. 
In both those who follow the adoption or IVF by donor route, the child is  related to the parent by no DNA or only by one parent. However, the child was part of the social fabric of the family.

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Offline DianaCanada

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Re: DNA - summary - worth it?
« Reply #49 on: Thursday 20 March 25 10:45 GMT (UK) »
When it comes down to it, for most of us, family history is a hobbie, and in most cases with hobbies, there is not a right way and a wrong way to approach it.  A hobbie is for relaxation and enjoyment, so do it whatever way suits you. 
I like to compare DNA to the boring but necessary side of history (politics, wars) to the more interesting family history research (how people lived, why they migrated, etc).  Both have their usefulness.

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Re: DNA - summary - worth it?
« Reply #50 on: Thursday 20 March 25 11:08 GMT (UK) »
The more stories, etc. the better. My interest began by listening to my mother  and her sister, sitting by the fire at Christmas with a dish of chestnuts, recalling  their shared memories of their parents, siblings, cousins, grandparents and the wider community. 
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Offline coombs

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Re: DNA - summary - worth it?
« Reply #51 on: Thursday 20 March 25 16:32 GMT (UK) »
I quite like finding a few surprises in my family tree. The 1921 census and 1939 register has thrown up some.

One hot summer day in late July 2004 I went to the Society of Genealogists in London on a few day trip there, and used their computers in the basement room, which also had lots of indexes of Boyds Marriage Indexes and census reels. I went on Ancestry to find my 2xgreat gran in the 1871 census in London, and it took some time due to the common name, and I found her aged 7 in Bow, East London and I got a surprised when it said her birthplace was given as Sussex, yet the next sibling aged 6 was said to be born London. Yet great, great gran had said in 1881, 1891 and 1901 census she was born in London, Stoke Newington. I then found her birth cert which proved it was mid Sussex and her parents moved to London soon after her birth, and her father had lived in Brighton for a time, originally from Kent.
Researching:

LONDON, Coombs, Roberts, Auber, Helsdon, Fradine, Morin, Goodacre
DORSET Coombs, Munday
NORFOLK Helsdon, Riches, Harbord, Budery
KENT Roberts, Goodacre
SUSSEX Walder, Boniface, Dinnage, Standen, Lee, Botten, Wickham, Jupp
SUFFOLK Titshall, Frost, Fairweather, Mayhew, Archer, Eade, Scarfe
DURHAM Stewart, Musgrave, Wilson, Forster
SCOTLAND Stewart in Selkirk
USA Musgrave, Saix
ESSEX Cornwell, Stock, Quilter, Lawrence, Whale, Clift
OXON Edgington, Smith, Inkpen, Snell, Batten, Brain