quote 1.
Apart from rare isolated occasions the y chromosome is passed down from
father to male children unchanged except for rare mutations.
Therefore
analyses of its DNA sequences provides a good tool for establishing
genetic linkages of male individuals. The extent of linkages is generally
expressed in terms of probabilities. However these are refined to such a
high degree of confidence that in most cases for genealogical studies,
linkages are generally accepted as matters of fact.
LM COMMENT:
Above is useful and succinct, Mick, thanks.
quote 2.
My attitude to the possible lack of continuity of a y chromosome is that it
does not detract from the family links except perhaps for the purists
who
demand a genetic connection through a male or female line. Adopted and
ex-nuptial children are very much family members and I believe they form
part of the genealogical history of all families.
LM COMMENT:
As a former psychologist, I find this interesting and relevant, because (for
example) research shows that the biggest predictor of the educational
success of a child is the educational attainments of the mother or major
caregiver of the child. (Not the genetic characteristics of the parent/s.)
In my view, children are born widely different, yes, but family-raising
influences are then immensely influential.
So genealogy, again in my view, can validly be used to track the
family-raising influences as well as the genetic characteristics. Why
not? Makes sense.
It should be considered too that there are scientist types out there who are
messing round with family heredity and DNA, some without the knowledge of
the family.
quote 3.
The point I am trying to make is that irrespective of any broad
regional linkages that are established by DNA analyses we still need
to
establish the links between individuals if we are to extend our
genealogical history.
LM COMMENT:
Agree.
THE ABOVE QUOTES COME FROM:
----- Original Message -----
From: "Mick Catley" <catleym(a)netspeed.com.au>
To: <CATLEY-L(a)rootsweb.com>
Sent: Saturday, June 18, 2005 3:03 PM
Subject: Re: [CAT...] DNA Testing
> G'day Tim and other listers who have contributed to this thread.
>
> From a very limited knowledge of genetics and DNA analysis I would like to
> add my comments to the discussion.
>
> Apart from rare isolated occasions the y chromosome is passed down from
father to male children unchanged except for rare mutations.
Therefore
analyses of its DNA sequences provides a good tool for establishing
genetic linkages of male individuals. The extent of linkages is generally
expressed in terms of probabilities. However these are refined to such a
high degree of confidence that in most cases for genealogical studies,
linkages are generally accepted as matters of fact.
>
> In the case of my Catley line, DNA analyses of my y chromosome and of
> those Catley males descended from a common male ancestor several
> generations removed would not establish links to my earliest
> Hertfordshire/?Cambridgeshire male antecedents. This is because the direct
> male line was broken several generations ago when an unmarried Catley
> daughter gave birth to a son who adopted the Catley name and was raised by
> her father as the father's son. I and many other Australian born Catley
> males would have the y chromosome of the father of the male ex-nuptial
> child, not that of the earlier Hertfordshire Catleys. If I knew the name
> of the father of the child I would pursue his family tree as avidly as I
> do the Catley line.
>
> I would be surprised if similar events such as formal and informal
> adoptions did not occur in other Cat(t)ley lines that would break the
> continuity of the inheritance of the y chromosome through successive
> generations of males. There is also the possibility that some male
> children were brought into a Cat(t)ley marriage by a wife or even to have
> had children from a male, other than her husband during her marriage. This
> reminds me of a quote from William Shakespeare's Merchant of Venice: "It
> is a wise father that knows his own child "
>
> My attitude to the possible lack of continuity of a y chromosome is that
> it does not detract from the family links except perhaps for the purists
> who demand a genetic connection through a male or female line. Adopted and
> ex-nuptial children are very much family members and I believe they form
> part of the genealogical history of all families.
>
> In relation to dna analysis of either the y chromosome or other
> chromosomes or mitochondria to establish linkages of the several Cat(t)ley
> branches in England, I would expect it would be useful in opening the way
> to search for the origins of our earliest recorded Cat(t)leys in the
> various regions. In the case of my earliest Hertfordshire record, which is
> a christening at Barley in 1710 there is a strong likelihood that the
> father (James Catley) came from neighbouring Essex where there is a number
> of earlier Catley records. Unfortunately I cannot link him to any of the
> Essex records that I have. The point I am trying to make is that
> irrespective of any broad regional linkages that are established by DNA
> analyses we still need to establish the links between individuals if we
> are to extend our genealogical history.
>