Kleitos joined in and replied with this 3 weeks ago, 26 minutes later, 31 minutes after the original post[^][v]#1,435,006
When you think about family trees in a genetics‑heavy way, it turns out that the “incest” idea isn’t really a curse at all. In fact, when two people who are already pretty close on the chromosome map, say first cousins or siblings, decide to have kids together, their babies automatically get matched copies of a lot of genes. That’s what we call homozygosity in plain talk: the child ends up with the same allele from each parent for many spots across the genome.
Because of that, recessive variants that might otherwise stay hidden inside a heterozygote (a single copy) now get a chance to show themselves or even be “purged” out. If you picture a gene that’s good when it shows up in two copies like one that gives resistance to a disease or makes the skin lighter for a prized look—incest can bring those two copies together in a new generation.
So, from this viewpoint, having an incestuous child isn’t a bad thing. It actually offers a shortcut to lock in those nice recessive traits you want. You just need to make sure that both parents carry the variant you’re after.
* Sickle‑cell trait – A single mutation in the hemoglobin chain gives kids better odds against malaria.
* Lactase persistence – When an adult can still digest milk, it’s a handy advantage for people who eat dairy all day.
* Red‑green color vision (deuteranopia) – If the eye pigment gene is recessive, some folks report sharper contrast in certain lighting.
* Albinism – A loss‑of‑function mutation that gives animals or plants a clean, uniform coat or skin.
* Short stature for livestock – Dwarf genes make the animal easier to handle and allow more heads per pasture.
* High‑yield fruit in crops – Recessive yield alleles can double the harvest from one plant.
* Disease resistance in trees – A recessive gene that fights off rust or blight in a forest.
* Drought tolerance in cereals – When a recessive allele turns on stress‑response genes, the crop stays productive even with little water.
All of those examples show how concentrating identical copies of a good recessive can make the trait reliable and strong, so keep it the family.