Three Unusual Modes of Inheritance in Niche - a genetics survival game

[Robb Plat]

Mendelian dominant and recessive genes, and sex-linked genes are the bread and butter of Niche - a genetic survival game. However, there some unusual game mechanics that result in strange modes of inheritance. In particular: the purple and yellow eye colour genes, the round and big ear genes, and the hemophilia and normal blood clotting genes. Using a reciprocal cross of male and female Nichelings, I determined that the eye colour and ear genes are based on whether the gene was passed down to the offspring from the mother. The hemophilia gene, however, was only passed down if the father was also a hemophiliac. Only the developers know whether these are intentional or unintentional modes of inheritance.

    I created two sets of Nichelings: #1) one wherein the mother had big ears and purple eyes, and #2) the other wherein the mother had round ears and yellow eyes. The fathers had round ears and yellow eyes, and big ears and purple eyes, respectively. Once crossed, cross #1 only resulted in offspring that had big ears and purple eyes, whereas cross #2 only resulted in offspring with round ears and yellow eyes. Each couple had about 20 children. I conducted this experiment in three separate game files. I assumed that there were no linked genes and that a pure-breeding population was not necessary for this experiment. The mutation menu was not used.
    We also conducted an F2 test cross in the same file, wherein the mothers were heterozygous for both ear and eye colour genes, and the fathers were homozygous for both genes. Again, we find that if the mother passes the gene to her children, it will be expressed as the dominant gene, whereas the same genes in the other reciprocal cross were recessive. I find this is strong evidence to support my theory that the purple and yellow eye colour genes, and the big around ear genes are based on a “maternal mode of inheritance.” This mode of inheritance results in the heterozygous offspring having an appearance more like the mother, i.e., the dominant ear and eye colour genes are always from the mother. I am not sure if this mode of inheritance is based on something that occurs in real life, but it occurs in this game.
    In a separate experiment, I crossed two sets of Nichelings: #1) one wherein both the mother and father are hemophilic, and #2) the other wherein only the mother is hemophilic. As this was an issue I encountered in the past (See Hemophilic Female, in Bug Reports, Robb Plat), I was fairly sure of the outcome. The first cross between hemophilic parents resulted in hemophilic children. This should be expected. Cross #2, however, showed something surprising… the male children from this cross all had normal blood clotting! This result was the same as my previous statement (Hemophilic Female, in Bug Reports, Robb Plat), wherein a hemophilic female had sons with normal blood clotting. In normal sex-linked genes, the sons get their Y chromosome (or in Niche, the “no gene”) that makes them “male”. Likewise, they get one blood-clotting gene from their mother, and in the case of the mother with two hemophilia genes, he should only get the hemophilia gene. However, we see that he appears to inherent both of his father’s blood-clotting genes, or the normal blood clotting gene comes out of nowhere!
    I gathered females that were heterozygous for the blood-clotting genes from cross #2 and crossed them to males with either #1) normal blood clotting, or #2) hemophilia. We found that this game mechanic worked normally, as we obtained female carriers of hemophilia, and normal offspring from cross #1, and hemophilic and normal males and females from cross #2. Unfortunately, I didn’t get any hemophilic males from cross #1 (which is not expected from a heterozygous mother), which I assume to be due to the power of RNG.
    Additionally, I crossed third-generation hemophilic female and normal-blood-clotting male (from the same game file). Again, we found that the male offspring had normal-blood clotting, as if from thin air. The first image below shows Lame, whose mate (Dukkudon) has normal-blood clotting, and her children. Based on the male/female names, you can see that the daughters are all carriers for hemophilia and the sons are healthy. In real life X-linked genetics, the sons should actually be hemophiliacs.

Robb Plat, Dipolma in “Biolology”

Supplementary photos:
The second and third images below show Ella, Lame’s younger sister, and Rata, their cousin. Ella and Rata are both homozygous for yellow and purple eye colour genes, respectively. The family tree shows that all of Ella’s children have the purple eyes as their recessive gene, whereas Rata’s children have recessive yellow eyes. Ella’s mate (Dukpri) is homozygous for purple eyes, and Rata’s mate (Takirpri) is homozygous for yellow eyes.
    Also note that Lame has big ears with round ears recessive, and Rata has round ears with big ears recessive. They inherited the dominant gene from their mother.
    Dukkudon’s genetics are shown in the fourth image.

[Sky]

Oooh, very interesting! I knew that purple and yellow eyes did this (I conducted my own experiments a long time ago), but didn't realize there were more genes with this characteristic. I don't know much about real genetics other than what I've learned from Niche - thanks for giving us a little biology lesson!

[Chiyanna]

This is fascinating! I don't know if this in intended or a bug, and furthermore no idea if it relates to real life! I hope someone can provide clarity on this

[Robb Plat]

22 hours ago, Sky said:

Oooh, very interesting! I knew that purple and yellow eyes did this (I conducted my own experiments a long time ago), but didn't realize there were more genes with this characteristic. I don't know much about real genetics other than what I've learned from Niche - thanks for giving us a little biology lesson!

You're welcome! I believe this also occurs with medium ears and round ears, and medium ears and big ears, but I have yet to fully experiment on these. In an old version, there was a strange occurrence with gills and big nose, but that has since disappeared and big nose is now dominant to gills.

[Sky]

8 hours ago, Robb Plat said:

You're welcome! I believe this also occurs with medium ears and round ears, and medium ears and big ears, but I have yet to fully experiment on these. In an old version, there was a strange occurrence with gills and big nose, but that has since disappeared and big nose is now dominant to gills.

I'm fairly certain that it does not happen between medium and big ears. I've never legitimately made it to Home Island however, so I don't have any nichelings with round ears to know it's mechanics.

[Modiano Urania]

9 hours ago, Sky said:

I'm fairly certain that it does not happen between medium and big ears. I've never legitimately made it to Home Island however, so I don't have any nichelings with round ears to know it's mechanics.

Medium ear is dominant over big ears, round ears Prevail over both when maternal inheritance. Bearyena ears are recessive to everything 

[Robb Plat]

On 5/9/2021 at 8:58 AM, Modiano said:

Medium ear is dominant over big ears, round ears Prevail over both when maternal inheritance. Bearyena ears are recessive to everything 

Yes, I also found that round ears prevail over both due to maternal inheritance. I took another look at my notes and medium ears are always dominant over big ears. Glad to know there are others who are interested in this stuff haha