How far back can throwback genes go?

[SarahS98]

They're genes that were dormant and it suddenly reappears after a long while. What can be made of this:

This might sound crazy but I have a friend that doesn't look anything like her Mexican parents. Both are the traditional brown-skinned folks with indigenous features, dark brown to black hair and mid-dark brown eyes. They have 3 kids. She's the oldest (25 years old) and the only one different from the others. She's white, has strawberry blonde hair and bluish-grey eyes. Absolutely nothing like her parents nor her 2 siblings, nor anyone in the family.

When she was born, they initially thought the nurses gave them the wrong baby. They requested a DNA test done but it showed positive; she's their biological child. The mother doesn't know of any whites in her family, none. The father is different case. It turned out there were a couple white ancestors in his side but they're long, long dead already. That's far back. Yet he turned out to be a carrier of the white genes.

How far back can genes go? Those ancestors from the guy's side are long dead already. How many generations can throwback genes skip?

[FreyaRed]

Very far. Often occurs specific appearance all 3 generations. Sister of my mother has 2 daughters and one one boy. One of the daughters has the same type of look like me and our grand mother says we both look like her mother in her twenties.
I guess these phenomena go even further back but 3 generations is what people usually remember and wide spread photography isn't older than 100 years.

[SarahS98]

I find genes such a unique topic. It's like rolling the dice and any can appear. Then just when you think a recessive trait is forever hidden, suddenly it's there again at any moment even if the ancestors who had those genes are long dead.

[FreyaRed]

99,98% of our Genes is inactive, it's not trash like some scientists believed decade ago, it's a library.

[purplepoppy]

You lose 50% of your genes for each generation. So you currently possess 25% from your grandfather, 12.5% from great grandfather, 6.25% from great great grandfather and so on..
The problem is genes are effective immortal and can resurface anytime.

[SarahS98]

yeah genes are so unpredictable. Just when you thought they were gone, nope they're there once again. It's like throwing the dice basically.

[Barracuda04]

I'm very aggressive, hot headed, vengeful but also CAN be cunning & creative & very aloof

The majority of my family are genuinely too nice, too naive, too trusting & none of them have anger issues or hold grudges like I do

[WanderingLoveWizard]

That's a good question. I thought throwback genes were pants that you used to wear in the 90s, so that's how smart I am

[grega239]

Very far. A small number of people have a muscle in their wrist that made us better climbers

[SarahS98]

It's crazy how genetics works out sometimes. My friend's father didn't think his old white ancestors could still pass their genes even when they're long dead already.