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That_Biology_Guy t1_iy4b1mj wrote

Generally yes, and the other answers already do a good job of explaining this, but I want to point out that there are real-world cases of genes which do not follow this model (and not just due to post-zygotic lethality of some genotypes as already mentioned). This is called segregation distortion or meiotic drive, and involves one allele (or often a group of linked alleles) increasing its own chance of being passed on at the expense of alternate alleles. Mechanistically, there are various ways this can work, including such a gene ensuring that it ends up in an egg cell rather than a polar body during oogenesis, or in some cases actively killing any gametes which don't share the same allele.

Besides these cases where meiotic drive is inherent to part of an organisms' genome, similar inheritance patterns can also be manipulated by parasites or pathogens. Wolbachia bacteria infect insects and are passed on from mother to offspring via eggs, and have famously developed ways to manipulate their hosts to produce only female offspring so that they don't end up in a male (which would effectively be a dead end). Humans have also been experimenting with the use of meiotic drives for artificial selection purposes, including some recent high-profile studies into the use of such a mechanism to reduce the ability of mosquitoes to transmit malaria.

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