TWINS

I hope I am not too far off the gene line of
thought with this question, in fact there may not
be an exact answer.

I have heard it said that "twins" run down the
female side of a family or something along those
lines. Just wondering whether this is exactly
true? Or if in fact then is any genetic link to
the probability of having twins?

Charani...

I've been told the same thing and looking at my father's line on the
male side, there have been 8 sets of twins over a period of some 140
years, only one set of which I know to have been identical and one set
known to have been non identical. None of the twins produced twins
themselves, AFAIK, and there were no twins in preceding generations.
The conclusion from that would tend to support the theory that it is a
female line trait. I've not followed any of the mothers' lines to see
if there are other twins in their families so the evidence from the
line I looked at is *far* from conclusive.

My first husband was one of non identical twins and there was no known
history of twins on either side of his family. A male friend is one
of identical twins and, again, there is no known history of twins on
either side of his family.

My own theory is that it's one of those things that can sometimes be
genetic and sometimes not, like some illnesses and conditions such as
autism which, according to some sources, is only hereditary and on the
mother's side but which, according to other sources, can be hereditary
and from either side but can also occur spontaneously.

Perhaps if you were to talk to your GP, s/he would be able to give you
a better idea or put you in touch with someone who would be able to do
so.

In the meantime you might find some of these sites helpful:

web-search produced over 100,000 results just from the UK by putting in
the search term "Multiple births" (include quotes)

michael lightfoot...

There are two entirely different kinds of twins, which I assume would have
two entirely different genetic probabilities.

Identical twins result from the splitting of an embryo in the very early
stages (can't remember exactly but I think it is pre-blastocyst.)
Non-identical twins result from multiple fertilisation, i.e. two eggs being
produced at once and both being fertilised and implanting.

I would assume that only the second case would have any genetic
predisposition and that would most probably be thru the female line.

I would suggest that web-search would be your friend here.

P.S. My mother was an identical twin and there are no others obviously in
her family for the several generations I have on record. I also have a
sister-in-law and brother-in-law who are twins. My wife doesn't know of
any others in her mother's family.

Example - my sister had twins. Our parents did
not nor did our grandparents on either side. In
the next generation you have to go back to our
mothers, fathers parents to find the next set of
twins in the family.

Charani...

I think it's one of those things that just "happens" for which there
is no real rhyme or reason but for which doctors feel they have to
assign a cause/reason.

Then her mother had twins (to her first husband
and we come from second husband) (GG Grandmother)

And her mother had twins, three generations in a
row. Now in this case it is mothers side to
mothers side, but as we closer to today it does
not appear to follow quite so.

Have we reduced the chances of twins by the simple
fact of reducing the number of children we have?
If it follows the female line does that mean that
one generation of males carry the genetic
possibility? As in our case we had to go back,
mothers, fathers parents. Ie by grandfather had
twin siblings and his grandparents had twins ie
his mother had twin siblings.

Any input very welcome. Thank you