[Praxising]

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Let's call it a "Martyr Gene". A tribe needs a martyr to survive, but the martyr would not live long enough to reproduce. Naturally, he wouldn't pass on the gene.


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Yes there are. The kind of thing you are talking about is called "altruism." The gene may not be passed by this carrier, but this sort of gene would be a double recessive, so that this individual's brother or sister, possibly having one copy, will pass that copy along.

Some lethal genes are not selected-for themselves, but get passed along in "piggyback" fashion. That is, they are located near a selected-for gene on the chromosome. When crossing over occurs, genes clumped together, get crossed together.

Sickle-cell genes are highly selected-for in populations where malaria is prevalent, even though having two of them is fatal. So having a single gene for sickle cell anemia is common to about 50% of those populations. That's a balanced polymorphism.

Gayness, for want of a better word, has selective advantages because we used to be a family-oriented culture. That is, we are social primates organized into family groups. The purpose of biological life is production and reproduction: staying alive and passing on your genes. To keep offspring alive long enough to reproduce themselves and pass on those genes, it makes reproductive sense to have as many resources as possible - protection, food, and so forth. Because siblings share genes, a non-reproducing ("gay") member of the family group, provides more protection for the young and can acquire more food resources. That member's genes reside in the offspring also.

Ejecting gay persons from our families and communities is counter to reproductive success for the population as a whole.