Trinity, on the baby i the UK, you said,
It might not be an albino mutation at all, just little surprises left in the gene pool over generations.
I had thought about that and yes, it can happen. But both parents are adamant that there have been no babies in the family as far as they can range back or range out, who are not all black. And given they have two kids (I think - or is it 3?) already, plus have family who have kids, and nothing REMOTELY like this has been seen - if you calculate the odds of both parents being heterozygous for white characteristics but having NOTHING show up in the number of births we're talking about (extended family too), then it brings it in direct comparison to the also very long odds on tis being a new gene, or a rare one appearing at random.
I am fascinated by genetics. When we were at uni we were shown a film on the complexity of genetics. Starting off simply, they showed a family with a German father and a Japanese mother (could have been easy child's classmate from elementary school). The father's family tree was full of blonde blue-eyed people exclusively. The mother's family tree was dark Japanese all the way back. Which colour scheme would prevail?
Of course, all the children were dark haired and dark eyed, as dark as their mother. And nobody was going to force the 'experiment' to an F1 X F1.
The other point - skin colour. From my observation, eye colour and hair colour are recessive and can, in an F1 X F1 generation, produce an average of one in 4 with the pure recessive and the other three (on average) with the dominant expressed. But how to hair and eye colour separate? Are they on the same allele? Or different ones? If on the same, how far apart? What are the chances of crossing over interfering?
And what about skin colour? In my observation, dark skin seems to be incompletely dominant. It can vary in degree from race to race (hate using the "r" word) because in Australian Aborigines, among the darkest people in the world, the dark skin "washes out" faster in successive generations than I believe African skin colour does.
This baby has appeared in a family whose eye colour, skin colour and hair colour has been consistent for generations and for extended family. And this baby's skin colour too, is fair. But her facial features are consistent, as far as I could see, with her brothers and sisters. And that tight curl! She is going to be a very unusual looking kid, the parents will be beating advertising firms off with a stick.
Trinity, your family sounds like a marvellous multicultural melting pot, a symbol of a world grown beyond borders and quarrels. What amazing variety!
In my own family, my mother was dark-haired, dark-eyed and short. She looked Middle-Eastern (but with a very nice nose). Maybe Italian or Greek. My father was tall, blonde and blue-eyed. He was also Universal Donor when in the army. That means blood group O negative.
Us kids - I think one brother has hair like Dad's, eyes like Dad's and a build like Mum. Another sister was like Dad but with straight hair, and eyes not quite blue, but grey. Another two sisters have hair a little darker, a sort of mid-brown.
The rest of us are almost black in hair colour. Two are as dark as Mum. They also have her dark brown eyes. The rest of us have pale eyes, but not blue. Grey, generally. Mine are the greenest. Two of us are almost as dark as Mum in hair, which has looked interesting with pale eyes.
Skin - one brother, one sister and I have the darkest skin. The rest tend to sunburn moderately easily, one as bad as Dad used to burn.
We have tried to trace the actual racial origins and can't ever really be sure, because we know there are skeletons in closets where the key has been thrown away; we will never know the truth. My mother was VERY dark-skinned, at a time when any hint of mixed race would have been a problem and a huge scandal. But looking at my siblings, we can work out a lot.
First, we can be sure we are all full siblings and offspring of both parents. Blood grouping has been interesting and there were a few lab mistakes (misinterpretations by family; corrected when they dug out the paperwork to check, or a later cross-match proved an earlier assumption wrong). Once we sat down and analysed it all, everything fitted together neatly. Second, our mother had to have a recessive blue eye gene as well as a recessive fair hair gene. Her blood group was A positive. But one of my sisters was Rh negative which caused her a lot of trouble. So our mother was carrying a recessive Rh negative gene. Heterozygous.
So come to me. I'm O positive. But I realised I MUST be heterozygous, as must every Rh positive sibling of mine. That means we need to check the Rh group of our daughters, because even these days an Rh negative mother can have problems with pregnancy if her blood group is not known.
My mother was strict about this - she watched her mother have miscarriage after miscarriage due to a condition called "haemolytic diseases of the newborn" which afterwards was discovered to be due to an Rh negative mother carrying an Rh positive baby, where the mother developed antibodies in her blood...wait a minute, that's where my mother got her Rh negative recessive gene from!
husband is Rh positive. But he COULD be heterozygous, we don't know. As you said, Trinity, a recessive gene can hide indefinitely. But it can't completely hide, not forever, not without cheating the laws of probability. We can predict with specific probability, the diminishing chance that husband is heterozygous. Because over the years each of our kids has been tested and found to be Rh positive. Sis-in-law's kids are both Rh positive (although if her husband is homozygous Rh positive then of course they would be).
This has reduced the chances a little that husband is heterozygous, carrying that hidden Rh negative gene. But not eliminated that chance.
If I went on to have another ten kids and all were Rh positive, that would greatly reduce the chance of husband carrying that recessive gene.
But we know, however, that regardless of husband's genetic status, I MUST be heterozygous (because Dad was a known Universal Donor, therefore Rh negative; plus a sister is negative. A brother too, I think). So our kids have a 50:50 chance at least, of carrying the recessive Rh gene.
And so it goes. But in the case of this baby, the genes involved are not necessarily connected closely, and not always fully recessive. Incomplete dominance is actually more common, even if it is only partial. So you get some degree of partial expression in, say, eye colour or skin colour. Even in hair colour. The more generations the genes get mixed up through, the more chance of a mixture or partial, often unique, expression of a combination, is what you get. I think this is why each of us is so unique - genetics is wonderfully complex, although it follows simple rules.
As I said - a fascinating topic. But the outcome is - we are all wonderfully unique and it is such a good thing that this is so.
I love my green eyes (in case you hadn't guessed). I don't like my skin colour much until I get a tan.
A funny story - when I was a little kid attending Sunday School, we sang the song, "Jesus Loves the Little Children" which includes the words, "red and yellow, black and white, they are precious in his sight," and the teacher explained that the black children were the Aborigines (OK, I saw them at school - teach says they're black so OK, they're black, even if it looks brown to me). The red were the American Indians, and I had a doll my sister had sent me, a lovely Indian maiden dressed in beads and suede and she was a beautiful reddish brown, I knew I would never get to be THAT colour!) and the yellow were the Asian kids, of whom I knew little, we had only one family living in our district and OK, yes, in summer their skin seemed a bit yellowish perhaps. I experimented with my eyes and knew I would never look Asian. And white - that was my Dad. My fair-haired sisters, perhaps. None of the were children any more. But not me, I was not white, more a dirty ochre. So Jesus didn't love me, because I wasn't any of the colours listed in the song. It made me sad. I was glad for all the other children of the world that Jesus loved, and of course they needed him to look after them when in some lands they were getting such a raw deal (including in Australia, it turned out) and I knew I had my parents to look after me, but they were very busy. I wanted that extra edge.
But at bath time, my sister used to allow me a little talcum powder on my tummy. Only a little. I noticed it made my skin look pearly white and beautiful. Surely that was what was meant?
I asked for more talcum powder but was not permitted; too expensive. So one night after bathtime, I stole the tin of powder and hid in the wardrobe, trying to powder myself a proper white so Jesus could love me. Yes, I got caught. yes, I got into trouble, No, I never explained because I felt sure they would not have understood.
Honestly - the things we put our kids through, without ever knowing...
Marg