Greetings to all, especially Justin!
The question of dominant genes can be difficult at times, as
different attributes have different types of expression.
At its simplest: each gamete from both parents give one gene
(thus two in the kid). If both parents give a dom. gene, the child will *in
most cases* express that attribute. If one parent gives a d-gene and the
other a recessive gene, then in most instances the d-gene will be
expressed. If both give r-genes, then the recessive trait will be expressed.
Certain traits are always are dominant: dark eyes over light,
dark hair over light, dark skin over light, tall over short, etc....
But then it can get tricky. Bear in mind that each parent only
gives one gene per trait. A dark-haired mother may be homozygous,
meaning both of her genes from her parents were dom., or she may be
heterozygous, meaning she has a dom. and rec. gene for that trait. She
can pass on *either one* to the child in that latter instance, meaning
that a hetero. dark-haired mother can pass on genes for a light-haired
child. Thus you can have the two dark haired parents with the blond kid....
Also, there is the problem of incomplete dominance. A homoz.
dark-eyed father, for example, with a homoz. light-eyed mother can
produce a green or hazel eyed child (or both, consider the actress Jane
Now, from what it sounds like Justin is describing, he is a mix
of ethnic groups that tend towards fair characterisitcs (Northern climes
and Hardy's theories about group genetic patterns). As such, if there is
a long line of fair-eyed, fair-haired, fair-skinned people in the family
tree, then the issue of dominance is realtively moot to begin with,
perhaps. This also increases the probability that those family members
who do not share the same charaacterisitcs are heteroz., thus there is
still a fairly high chance that the kids will get the
rec./fair-hair,-eye, -skin genes, epsecially if they're "mating" (so to
speak) with someone with all these rec. qualities.
Other issues that come into play are not so easy to determine,
such as dom. vs. rec bone. structures and the like, which sounds as well
like what Justin was aiming at (yes?). I don't know as much about these,
but my own experience has ather shown that at least a certain group of
bone structures (facial) in some friends of mine of Scottish ancestry are
severely dom. in the family tree. The daughter is the image of the
grandmother, who herself resembled the grandmother, and so on. I know a
number of Arabs where the same pattern of dom. genes occurs in the family.
So, in the end, it might not be so much "Celtic" blood or DNA as
such, but the particular pattern of rec. and dom. genes that have been
running through the family tree, along with certain almost agressively
dom. genes on various points in the DNA, Scottish, Celtic, or otherwise
in nationality/ethnicity of origin.