Sims 4 Genetics

JulianneALee · April 2016

Back when I was playing Sims 2 (I've never played Sims 3) the genetics system was obvious and easy to understand. Each trait for each Sim involved two alleles; one expressed and the other not. The child received one allele from each parent, and the dominant trait of the pair would show in the child. Townies and Sims made in CAS always started out with the two alleles in each pair the same. It was easy to track the recessive genes down the generations and determine which gene was the unexpressed one in many of the Sims. But now, in Sims 4, random genes are popping up in the children of Townies and CAS Sims. Especially the Goth family. My question is: does anyone know if there's an official word on how the genetics work in Sims 4? Do they still have alleles and dominant/recessive genes?

meeoun · April 2016

JulianneALee wrote: »

Back when I was playing Sims 2 (I've never played Sims 3) the genetics system was obvious and easy to understand. Each trait for each Sim involved two alleles; one expressed and the other not. The child received one allele from each parent, and the dominant trait of the pair would show in the child. Townies and Sims made in CAS always started out with the two alleles in each pair the same. It was easy to track the recessive genes down the generations and determine which gene was the unexpressed one in many of the Sims. But now, in Sims 4, random genes are popping up in the children of Townies and CAS Sims. Especially the Goth family. My question is: does anyone know if there's an official word on how the genetics work in Sims 4? Do they still have alleles and dominant/recessive genes?

The child is given random phenotypes from both parents. No recessive, no dominate genes.

JulianneALee · April 2016

Thanks for answering, meeoun. Okay, so they do have alleles, but no traits are dominant or recessive. That answers half of it. What about CAS Sims? Do they get two of the same alleles, or does the game randomly pick a second one for you? I hear that in Sims 3 they had "mutations." Is that what's going on here, or is CAS sneaking in extra genes?

feetinstockings · April 2016

I maybe stupid here, but in CAS you give your sims what traits you want, I don't know of the game putting in hidden genes.
are you talking about traits or genes as in how they look??

Cement · April 2016

Genes in 4 don't seem to really follow basic genetic rules, I feel. It's more like following ratios rather than genes when you have children in this game. Everyone's genes seem to be immediately dominant, so if you have a family that for some reason has two generations of purely blond hair and that person marries someone with a different hair color, like black, blond would have a higher chance of showing up rather than black, especially when there's only like one generation of black hair.

Townies have random kids with random genes. They don't follow a pattern when they're generated, but because of familial ties, they'll carry on genes of their relatives, which applies to adopted children too.

In-game children you made via Try for Baby or if you use MC Command Center's insemination are more or less interesting since there are slight chances of them obtaining features that were only prevalent in their great/grandparent. (Like they'd get their hair color or even their body type, sometimes even look 90% like them if their parents are wildly different in appearance). CAS sims generally follows the same pattern, it seems. Extra genes are usually explained by the sim's background. For example, some noses look different on males than on females. They're usually larger and/or more defined on men, when in females most features are generally softer.

Polyrhythm · April 2016

I don't think TS4 has the genetic system TS2 has with dominant/recessive genes, alleles, etc.
Based on the kids I've had its usually a general mashup of the parents.
My sim with red hair and brown eyes married someone with black hair and green eyes. Their kids both had red hair, but one had brown and the other had green eyes. The one with green eyes had more features from her dad.
Then the redhead, brown eyed sim married a blond, blue eyed sim and they had a son with red hair and a daughter with blonde, both with brown eyes. The son looks like his dad, daughter looks like her mom.

The original sim I started out with though had blue hair and her husband had brown hair. That's where the random red hair came from I guess, since kids can't have blue hair. I was still kinda sad to see the red become so prevalent though when it initially wasn't there qq

feetinstockings · April 2016

I've been playing the Goths, I changed Bella's hair to red, then I did try for baby and when the baby grew into a child she had the red hair I had given to Bella, but she had her fathers colour eyes.
so the genes can be changed. Wish I could change Bella's bust, I don't want her daughters having that size bust.

pixiejuice · April 2016

From what I've seen, I don't think it's recessive and dominant genes or anything as complex as TS2 had. But they can inherit features from their grandparents. I once had a child inherit his grandfather's very distinctive nose, which his mother didn't get and was nothing like his father's nose. I don't think it's that the mother carried a recessive gene for it, but just that the grandfather was in the random pool of genetics that the child could inherit.

Sha2520032003 · April 2016

I've never understood how genetics work in TS4. The hybrid Sim in my avatar (Shayne) has green skin, blond hair. She married a Sim that had white skin and brown hair. The daughter had blue skin and blonde hair & favored her mother in appearance while the son had brown skin and brown hair and looked like the dad. Both parents have blue eyes, but the son has brown eyes. Shayne's father had brown eyes, so I was thinking maybe the son took after his grandfather, or maybe it's just completely random.

Here's a pic of the parents:

& he's a pic of their adorable children:

feetinstockings · April 2016

Sha2520032003 wrote: »

I've never understood how genetics work in TS4. The hybrid Sim in my avatar (Shayne) has green skin, blond hair. She married a Sim that had white skin and brown hair. The daughter had blue skin and blonde hair & favored her mother in appearance while the son had brown skin and brown hair and looked like the dad. Both parents have blue eyes, but the son has brown eyes. Shayne's father had brown eyes, so I was thinking maybe the son took after his grandfather, or maybe it's just completely random.

Here's a pic of the parents:

& he's a pic of their adorable children:

makes you wonder where the blue skin comes from in their genetics.

Sha2520032003 · April 2016

@feetinstockings Yes it does. I've played with hybrid Sims before and they either looked exactly like the hybrid Sim or the other parent. Both of the kids were a surprise! But I must say I love the unexpected. I'm currently playing them. The future generations will definitely be interesting for this family.

Polyrhythm · April 2016

One thing I've noticed when messing around with eye colors in Sims4Studio is that while the reddish eyes have their own color tag (amber), purple eyes don't and are also tagged as amber. Because of that two sims with purple eyes could have kids with red eyes. Seems like a strange oversight.

feetinstockings · April 2016

Sha2520032003 wrote: »

@feetinstockings Yes it does. I've played with hybrid Sims before and they either looked exactly like the hybrid Sim or the other parent. Both of the kids were a surprise! But I must say I love the unexpected. I'm currently playing them. The future generations will definitely be interesting for this family.

I've just made a new alien family, I'm a little hooked on the alien sims at the moment. anyway I made one child genetically their child, but mum is preggies so I'm wondering what colour the baby will be. his blue and she is light purple. have fun with yours.

Scobre · April 2016

For supernaturals at least, the Sims 4 has a hybrid system like the Sims 2 had. So like Sims that are part alien, as more generations progress, Sims can look more and more human as more human blood is bred into them. I can't wait to see what will happen as more life states are introduced.

Sha2520032003 · April 2016

feetinstockings wrote: »

Sha2520032003 wrote: »

@feetinstockings Yes it does. I've played with hybrid Sims before and they either looked exactly like the hybrid Sim or the other parent. Both of the kids were a surprise! But I must say I love the unexpected. I'm currently playing them. The future generations will definitely be interesting for this family.

I've just made a new alien family, I'm a little hooked on the alien sims at the moment. anyway I made one child genetically their child, but mum is preggies so I'm wondering what colour the baby will be. his blue and she is light purple. have fun with yours.

Awesome, have fun with your family as well! I love my aliens lol

JulianneALee · April 2016

One thing I've noticed when messing around with eye colors in Sims4Studio is that while the reddish eyes have their own color tag (amber), purple eyes don't and are also tagged as amber. Because of that two sims with purple eyes could have kids with red eyes. Seems like a strange oversight.

Polyrhythm: What do you mean by "tags,?" I've suspected something like a grouping of colors for eyes and hair, but nobody has said anything like that until you just did. What are "tags," and how do you think they work? What is Sims4Studio? How have you identified that they exist? This could explain some of the randomness I found in my Goth family.

Polyrhythm · April 2016

JulianneALee wrote: »

What do you mean by "tags,?" I've suspected something like a grouping of colors for eyes and hair, but nobody has said anything like that until you just did. What are "tags," and how do you think they work? What is Sims4Studio? How have you identified that they exist? This could explain some of the randomness I found in my Goth family.

Sims4Studio is a program for creating custom content. You can open up any of the existing hair, eye colors, etc with it however and it shows what color tags are assigned to each. They're for genetic purposes.
These are all the hair colors

These are the eye colors

The purple eyes being tagged as amber though is the only thing weird though, everything else is tagged correctly. This is why some CC hair/eye colors can cause wonky genetics, if it's a color that's nonexistent in the tags or if the creator tagged the wrong color (like red CC hair tagged as brown)

JulianneALee · May 2016

Okay, I see this isn't what I thought. But it might explain some of my wonky colors showing up. I'll have to go back and track down what's been going on with my purple and amber eyed Sims. So...according to your screen capture, the Hazel Olive Green, Hazel Blue Dark, Dark Blue, Hazel Gray Brown, and Purple don't have their own tags. Can you tell me what tags those colors do have? This would absolutely explain the inheritance pattern of some of my Sims.

JulianneALee · May 2016

I see that all the hair colors have corresponding tags. But with the eye colors there are five colors that don't have corresponding tags (Hazel Olive Green, Hazel Blue Dark, Dark Blue, Hazel Gray Brown, Purple), and three tags without corresponding eye colors (Golden, Honey, Hazel). All except the Purple can possibly fall under "Hazel," and you say Purple is tagged as Amber. That leaves me to wonder what Golden and Honey are doing there, and whether any of the Hazels are tagged with those. Are there any NPC type Sims with yellow eyes?

Feyona · May 2016

@JulianneALee I think that creators put these tags for future purposes. Probably these colors were found somewhere in code (like witch tag was found in the code) so they put these tags in the program. I can think only of werewolves as creatures who can possibly have honey or golden eyes.

Smiles70021 · May 2016

My identical twin boys look exactly like their mother. But I did read somewhere that when they age into teens sims face change a bit. Is this true?

JulianneALee · May 2016

Feyona Yeah, that sounds probable. I have downloaded Sims 4 Studio, but I don't know how to open the eye colors to identify all the tags. Is there someone who can tell me for sure whether I'm right about the four stray Hazels being tagged Hazel? If I were certain, then I could sort through the four generations of my game and see what's actually going on with inheritance.

Feyona · May 2016

@JulianneALee , choose "Create standalone CAS" and press CAS button. You'll get menu with all game content. Don't forget to put creator's name (it's a mandatory). Then choose gender "ALL", for age choose "all" or "adult" (doesn't matter actually) and in part type choose "eye color" and you'll get all game eye colors including eyes of evil twin and alien eyes. Then move mouse over the picture of each eye and you'll see corresponding names. I hope it helped. Please see pictures in spoiler tags.

Polyrhythm · May 2016

Here's the in-game eye color swatches and their tag names.

Top row, left to right: black, dark brown, brown, light brown, hazel green, light green, light green, green, hazel blue
Bottom row, left to right: hazel blue, aqua, light blue, blue, gray, gray, light brown, amber, amber

So there are no eye colors that use the hazel, golden or honey colors, and several use the same color tag, which will lead to things that seem off in genetics.
Like two parents with the duller light green eyes can have a child with the brighter green ones

Or parents with the grayish hazel blue eyes can have a child with the more blue looking ones

shinys212 · May 2016

Thank you for these posts! Even though you guys don't completely solve my problem, i'm now sure this has something to do with the way the eye colors are tagged.

I have a problem with the top row hazel blue. I'm doing a 100 baby challenge, and the sim that I started it out with has those eyes. She has had 20 kids now and none of them have those eyes. They always have their fathers eyes or the light brown ones... It's so irritating!

For now I have been using the cas cheat to give them their mothers eyes. But it kind of feels like cheating, which I don't like to do in my games

Feyona · May 2016

@shinys212 do you have any custom eyes in your mods folder? It's a known glitch that kids get brown eyes if there is something in mods folder that conflicts

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Sims 4 Genetics

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